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JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

VOLUME XXXIX JULY, 1942 

CONTENTS 

The Carbon Situation and Copper Conservation 

E. A. WILLIFORD 3 

Experiences in Road-Showing Walt Disney's Fantasia 

W. E. GARITY AND WATSON JONES 6 

The Future of Fantasound EDWARD H. PLUMB 16 

Mobile Television Equipment 

R. L. CAMPBELL, R. E. KESSLER, R. E. RUTHERFORD, 

AND K. V. LANDSBERG 22 

The Application of Potentiometric Methods to De- 
veloper Analysis JOHN G. STOTT 37 

Continuous Replenishment and Chemical Control of 
Motion Picture Developing Solutions 

H. L. BAUMBACH 55 

The Practical Aspect of Edge-Numbering 16-Mm Film 

H.A.WiTT 67 

A New Electrostatic Air-Cleaner and Its Application to 
the Motion Picture Industry HENRY GITTERMAN 70 

Current Literature 75 



Society Announcements 77 

(The Society is not responsible for statements of authors.) 



JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

SYLVAN HARRIS, EDITOR 
Board of Editors 

ARTHUR C. DOWNES, Chairman 

JOHN I. CRABTREE ALFRED N. GOLDSMITH EDWARD W. KELLOGG 

CLYDE R. KEITH ALAN M. GUNDELFINGER CARLETON R. SAWYER 

ARTHUR C. HARDY 

Officers of the Society 

*President: EMERY HUSE, 

6706 Santa Monica Blvd., Hollywood, Calif. 
*Past-P resident: E. ALLAN WILLIFORD, 

30 E. 42nd St., New York, N. Y. 
*Executive Vice-President: HERBERT GRIFFIN, 

90 Gold St., New York, N. Y. 
** Engineering Vice-President: DONALD E. HYNDMAN, 

350 Madison Ave., New York. N. Y. 
*Editorial Vice-President: ARTHUR C. DOWNES, 

Box 6087, Cleveland, Ohio. 
** Financial Vice-President: ARTHURS. DICKINSON, 

28 W. 44th St., New York, N. Y. 
* Convention Vice-P resident: WILLIAM C. KUNZMANN, 

Box 6087. Cleveland, Ohio. 
* Secretary: PAUL J. LARSEN, 

1401 Sheridan St., N. W., Washington, D. C. 
*Treasurer: GEORGE FRIEDL, JR., 

90 Gold St., New York, N. Y. 

Governors 

*MAX C. BATSEL, 501 N. LaSalle St., Indianapolis, Ind. 
**FRANK E. CARLSON, Nela Park, Cleveland, Ohio. 

*JOHN G. FRAYNE, 6601 Romaine St., Hollywood, Calif. 

*ALFRED N. GOLDSMITH, 580 Fifth Ave., New York, N. Y. 
**EDWARD M. HONAN, 6601 Romaine St., Hollywood, Calif. 

*I. JACOBSEN, 177 N. State St., Chicago, 111. 
**JOHN A. MAURER, 117 E. 24th St., New York, N. Y. 

*LOREN L. RYDER, 5451 Marathon St., Hollywood, Calif. 

* Term expires December 31, 1942. 
** Term expires December 31, 1943. 



Subscription to non-members, $8.00 per annum; to members, $5.00 per annum, included 
in their annual membership dues; single copies, $1.00. A discount on subscription or single 
copies of 15 per cent is allowed to accredited agencies. Order from the Society of Motion 
Picture Engineers, Inc., 20th and Northampton Sts., Easton, Pa., or Hotel Pennsylvania, New 
York, N. Y. 

Published monthly at Easton, Pa., by the Society of Motion Picture Engineers. 

Publication Office, 20th & Northampton Sts., Easton, Pa. 

General and Editorial Office, Hotel Pennsylvania, New York, N. Y. 

Entered as second-class matter January 15, 1930, at the Post Office at Easton, 

Pa., under the Act of March 3, 1879. Copyrighted, 1942, by the Society of Motion 

Picture Engineers, Inc. 



THE CARBON SITUATION AND COPPER CONSERVATION* 

E. A. WILLIFORD** 



The meeting of the Atlantic Coast Section of the Society on May 21st was devoted 
to the question of "Wartime Conservation in Theater Projection" The paper that 
formed the basis of the meeting has already been published, in last month's issue of 
the JOURNAL. 

At the end of the presentation, the following discussion, on the carbon situation and 
the conservation of copper, was contributed by Mr. Williford. 

I appreciate your request that I tell you something about the car- 
bon situation. Fortunately, the basic materials for the manufacture 
of projector carbons are petroleum products, of which ample supplies 
are available. We do not see any possibility of there being any 
shortage of these materials. 

For high-intensity type carbons, however, certain rare-earth 
minerals are used to produce the brilliant white source of light, and 
these rare-earth materials have been supplied principally from India. 

Before America entered the war there was several years' supply 
of this material in the United States and, according to my latest 
information, there is still several years' supply here. More is coming 
in as shipping facilities are available. Brazil also contains large 
deposits of these minerals which could be used if the Indian source 
is cut off. There are even deposits of this material in the United 
States, although the costs of obtaining it would be quite high as 
compared with Indian costs, or even Brazilian costs. In any event, 
there does not appear, at this time, to be any prospective shortage 
of these rare-earth minerals. 

For "Suprex" carbons, high-intensity negatives, and a few other 
types of projector carbons it has been necessary to curtail our use 
of copper in the copper plating. As you know, the war needs for 
copper are greatly in excess of any visible supply and it is up to every 



* Presented at the meeting of the Atlantic Coast Section at New York, N. Y., 
May 21, 1942. 

** National Carbon Company, New York, N. Y. 



4 E. A. WlLLIFORD [J. S. M. P. E. 

one of us to do all we can to use as little copper as possible, and to 
salvage every bit that we can. 

For some months now we have been using our advertising space 
to promote the idea of burning carbons at lower current, peeling the 
copper plating from any butt ends remaining, and saving the copper 
drippings from the lamp-houses. Many projectionists have been 
doing this and, in accordance with War Production Board instruc- 
tions, have turned these peelings and drippings over to scrap dealers, 
even though the value might be so small that they receive no com- 
pensation in return. 

In our own Research Laboratories intensive studies have been 
given to reducing the amount of the copper plating, and also elimi- 
nating it entirely, if possible. For the moment, we are producing 
thinner plated carbons, and as of today, our stocks of the 6.5-mm X 
9-inch Orotip "C" negatives of the older standard plating thickness 
type have been exhausted. Within a few days all other types of 
carbons with the standard plating will, likewise, be out of stock and 
shipments thereafter will be of the new thinner plated variety which 
we have called Victory carbons. 

The industry is extremely fortunate in that some of our research 
program over the past few years culminated very recently in the 
development of a new 8-mm diameter "Suprex" positive. Even 
with the Victory plating, these carbons will give the same light on 
the screen as the old carbons with 5 amperes less current and with 
approximately 20 per cent saving in carbon consumption. At 65 
amperes, which is the maximum current for both the old and the new 
Victory carbons, the screen light is considerably greater and the 
carbon consumption also is considerably less. 

In the case of the 7-mm positive 6-mm negative combination, 
it will be necessary to reduce the current on these carbons with result- 
ing loss in screen light. The amount of this reduced illumination is 
only about 15 per cent, however. If the power source can be operated 
at 56 amperes and the new 8-mm 7-mm trim used, the same screen 
illumination can be obtained with a saving of about 30 per cent in 
carbon consumption, but at an increased power consumption of 
approximately 12 per cent. 

These new carbons will be marked with white ink to distinguish 
them from the standard product which has been labelled with blue 
ink. The maximum permissible current will be printed on each 
carbon beside the trade-mark. The unit carton will have a special 



July, 1942] CARBON SITUATION AND COPPER CONSERVATION 5 

label indicating not only the maximum allowable current for the 
type of carbons contained in the package, but also showing the 
weight of copper drippings that can be recovered from the lamp- 
houses, from a package of 50 such carbons. This weight has been 
carefully calculated, based on the minimum thickness of copper 
plating applied, and allowing for about 10 per cent loss through 
carelessness in handling. It represents what can be readily salvaged 
and unless or until the government advises you otherwise, we suggest 
that you save these drippings and any peelings from the butt ends of 
carbons until you have a quantity sufficient to give or sell to a scrap 
dealer. At the present time government regulations do not permit 
you to dispose of this copper scrap to any other person. The copper 
plating on the new Victory carbons is so thin that it is doubtful 
whether any plating remaining on the stubs can be salvaged. On 
the other hand, by the use of carbon savers, all carbons can be burned 
to stubs of not over 1 inch in length, in which case the amount of 
copper thus lost will be very small indeed. 

We are glad to have been able to make this constructive change 
in the interests of copper conservation for the promotion of our 
national war effort and know that each t>f you will cooperate in this 
program of copper conservation, even though it may mean extra work 
and some inconvenience to you in your daily job. 



EXPERIENCES IN ROAD-SHOWING WALT DISNEY'S 
FANTASIA* 



WILLIAM E. GARITY** AND WATSON JONESf 

Summary. A discussion of the various problems encountered in the road-show- 
ing of "Fantasia" with the multiple-track Fantasound equipment. The experiences 
and conditions encountered are presented as a guide for the further development of 
this very important field. It is expected that this system will add greatly to the dramatic 
presentation of pictures and will, in some form, replace our sound-reproduction sys- 
tems. 

Fantasia was the result of an idea that grew over a period of three 
years from a "standard" one-reel "short" to a multi-million dollar 
road show that required the largest outlay of sound equipment that 
has been used commercially in the theater to date. Many new 
methods and procedures were found necessary to achieve the results 
that were desired for the final product. These new methods and 
procedures applied not only to the sound technic but the pictorial 
aspect as well. In order to appreciate fully the amount of artistic 
and engineering work that was expended on Fantasia it is interesting 
to review some of the highlights of our experience over a period of 
about three years prior to the premiere of the picture in New York on 
November 13, 1940. 

During the latter part of the year 1937 Walt Disney conceived the 
idea of making a cartoon "short" using as a basis some well known 
musical selection that lent itself to cartoon animation. A serious 
effort was made to interpret the composer's musical ideas pictorially 
as well as to record music that would blend into the picture and 
provide a combined, indivisible form of entertainment. The Sorcerer's 
Apprentice was chosen for the original, and was recorded in January, 
1938, by 100 musicians conducted by Leopold Stokowski. 

The Sorcerer's Apprentice was recorded at the Pathe Studio, Culver 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received May 
1, 1942. 

** Walt Disney Studio, Burbank, Calif, 
t RCA Manufacturing Co., Hollywood, Calif. 

6 



ROAD-SHOWING FANTASIA 7 

City, Calif., on a production stage that was altered acoustically for 
the occasion. Our theory was to make a multiple-channel recording 
that would have satisfactory separation between channels so that 
suitable material would be available from which to obtain any de- 
sired dynamic balance in re-recording the original material. In the 
effort to obtain satisfactory separation between channels, a semi- 
circular orchestra shell was constructed in the stage. The shell was 
then divided into five sections by means of double plywood partitions. 
Two difficulties were encountered with such a set-up; one was poor 
low-frequency separation; the other was the inability of the musi- 
cians at the rear of the sections to hear the music from the other 
sections, to such an extent the tempo was impaired. This condition 
was improved, at a sacrifice in separation, by having the musicians 
move nearer the front of the shell sections. As work progressed on 
the animation and re-recording of the material, Walt Disney decided 
to add other musical selections and to present a full-length presenta- 
tion that would be outstanding in its scope. It was at this time that 
discussions first took place regarding special equipment for the show- 
ing of the picture. The goal that we hoped to reach was the repro- 
duction in the theater of a full symphony orchestra with its normal 
volume range and acoustic output as well as the illusion that would 
ordinarily be obtained with a real orchestra. Many ideas were 
investigated, equipment was designed, and tests made of various 
combinations of equipment that would give the ultimate in a sound 
and picture entertainment. For a further description of these in- 
vestigations the reader is referred to a paper on "Fantasound" by 
Garity and Hawkins in the August, 1941, JOURNAL. 

The best combination of music and recording conditions was de- 
sired for the additional selections, and it was decided therefore to 
abandon the Sorcerers set-up .and to record the Philadelphia Orchestra 
in the Academy of Music in Philadelphia. This decision had two 
points in its favor; one being the fact that the acoustic properties of 
the Academy are excellent, and the second being that this orchestral 
group has been organized for many years and their musical talent is 
rated as one of the highest. At the time of the decision to do the 
recording at Philadelphia it was not known exactly what the music 
requirements would be in order to achieve the dynamic and musical 
balance necessary to the picture story being told. So that this re- 
quirement might be fulfilled in the re-recording of the original ma- 
terial, a multiple-channel recording was made and it was, of course, 



W. E. GARITY AND W. JONES [J. S. M. P. E. 



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July, 1942] ROAD-SHOWING FANTASIA 9 

necessary to install nine studio-type recording channels in the Acad- 
emy. 

The recording machines were located in the Academy basement, 
and since the inside of the building is constructed of wood, many 
safety measures had to be taken. No more than eighteen rolls of raw 
stock were allowed in the Academy at one time, and in order to insure 
a sufficient quantity of film for each recording session, a film-delivery 




FIG. 2. Installation in the Carthay Circle Theater, Hollywood. 

truck was converted into a suitable loading room and was parked 
outside the building during recording sessions. All loading and un- 
loading was done in this truck. The work of installation and record- 
ing was supervised by the authors, who spent the entire spring of 1939 
in the Academy basement. 

EQUIPMENT PROBLEMS 

To appreciate fully some of the problems encountered in the design 
of the road-show units it is necessary first to see what constitutes a 
complete unit. Each Fantasound road-show equipment consisted 



10 W. E. GARITY AND W. JONES [J. S. M. P. E. 

of sound reproducers, amplifiers, and loud speakers so arranged as to 
reproduce sounds from a multiple sound-track film run in synchro- 
nism with the picture film. The level and distribution of sound to the 
various stage and auditorium loud speakers was automatically varied 
in a predetermined manner by means of the control-tone and program 
sound-tracks on the multiple sound-track film. Fig. 1 is a block 
diagram of the Fantasound equipment as used for the reproduction 
of Fantasia. This system consisted of three separate program ampli- 
fier and loud speaker channels, and a control- tone channel; two 
selsyn-operated multiple sound-track reproducers; two selsyn - 
operated sound-heads ; two selsyn distributors ; three two-way stage 
loud speaker systems; auxiliary theater auditorium loud speakers; 
and amplifiers and necessary operating facilities. Fig. 2 shows the 
equipment as installed in the Carthay Circle Theater, Hollywood. 

Power Supply. All equipment was furnished for 60-cycle power. 
The amplifiers and power-supply units required 110-125-volt single- 
phase current; the selsyn distributor 220 volts, three-phase. Where 
power fulfilling these requirements was not available, the necessary 
rotating equipment or transformers were supplied for the particular 
job. In order that the line- voltage variations would have the least 
effect upon the sound output level, the a-c input voltage to the 
exciter-lamp supply was regulated, and regulated supplies were em- 
ployed to furnish plate power for the variable-gain amplifiers and 
tone rectifiers, and polarizing voltage for the phototubes. 

Stage and Projection Room Space. Due to the fact that each road 
show unit consisted of eleven 62-inch racks of amplifiers and power- 
supply units, in addition to the other items indicated in Fig. 1, there 
existed quite a problem in finding space in the average theater for the 
various items. The wiring and operating facilities of the equipment 
were so arranged that it was necessary to install a minimum of six 
racks in the projection room in addition to the two multiple sound- 
track reproducers. This was further complicated by the fact that 
many theaters available and suitable for road-show attractions 
generally did not have much of a projection room, if any. Power- 
switching facilities were contained in one of the racks installed in the 
projection room so that the additional five racks could be mounted 
outside the projection room if space was not available therein. The 
two selsyn distributors on which were mounted the necessary starting 
and remote-control devices were located outside the projection room 
where conditions permitted. The speaker-field supply rack was so 



July, 1942] ROAD-SHOWING FANTASIA 11 

arranged that it could be mounted on the stage proper, near the 
loud speakers, in order to conserve wire runs; however, in some 
theaters this was not advisable due to the differences in local rulings 
as to whose duty it was to turn on and off the power to the rack. 
Space behind the picture screen was generally available for the loud 
speaker systems. The screen had to be moved up or down stage in 
many theaters in order to get the best distribution of sound. The 
three loud speaker systems required an average width of 44 ft, and it 
was always necessary to change the masking draperies on either side 
of the screen in order to obtain satisfactory sound transmission from 
the side loud speakers. 

Inter- Apparatus Connections. The model road-show unit that was 
first manufactured made use of Cannon-type plugs and fittings for 
all inter-apparatus connections. Due to the large number of cable 
connections necessary, it was impossible to have a different type of 
plug for each circuit, and there was always the possibility and hazard 
of plugging a cable into the wrong position, with resulting damage to 
equipment. After a nation-wide survey of city inspectors concerning 
the use of rubber-covered cables and plugs on equipment located in 
projection rooms in a theater on a road-show basis, we found there 
existed many rulings, some definite and others rather vague. Some 
city inspectors would agree to the use of rubber-covered cables 
provided the show did not run longer than thirty days or so. Others 
would not agree to rubber-covered cables in the projection room on 
any condition. In one installation no exposed conduit was permitted, 
due, no doubt, to a safety measure as well as a "projection room 
beautification program." For the foregoing reasons all cables and 
plugs were eliminated and Greenfield or rigid conduit was used for all 
installation wiring. 

Emergency Features. Since this was a major project so far as the 
amount of sound equipment to be used was concerned, and it was to 
be a "two-a-day" show with road-show prices, some emergency 
feature was desired in case of failure of the Fantasound system. In 
case of failure of the control-tone variable-gain part of the system, 
switching facilities were provided whereby the control-tone section 
could be by-passed and the three program channels could operate 
with the volume range that existed on the program tracks themselves. 
This still involved the use of a large percentage of the equipment, and 
further simplification of the emergency feature was thought desirable. 
The sound-track on the picture film was a standard variable-area 



12 W. E. GARITY AND W. JONES [J. S. M. P. E. 

composite of the sound material that was located on the three program 
tracks of the multiple-track film. By means of one switch which 
actuated a relay system, the sound was transferred from the Fanta- 
sound set-up to the emergency channel, making use of the standard 
sound-track on the picture film, the emergency amplifier, and the 
center-stage loud speaker. Theater experience proved that the 
equipment was very reliable, and even though the number of com- 
ponent parts in the road-show unit was many times that of a standard 
theater set-up, the number of sound outages were no more than is 
experienced in a standard theater. The sound outages that did occur 
were caused in the majority of instances by operating failure rather 
than equipment failure. Such successful performance with the large 
quantity of equipment involved indicates the high degree of per- 
fection that has been reached in present-day engineering and manu- 
facture of theater sound equipment. 

Audio Power Requirements. The success of any high volume range 
reproduction depends greatly upon having equipment with sufficient 
undistorted power-handling capacity. The Fantasound equipment 
has three 60-watt amplifiers for the stage speakers. This proved 
satisfactory for the majority of installations ; the New York unit used 
additional power. The full capacity of the system was usually 
reached on peak levels during the performance. 

Equipment Testing and Program Level Adjustments. The experi- 
mental work on the multiple-channel reproducing system indicated 
that slight differences in level between channels would give the effect 
of motion of the sound from one loud speaker to another. For this 
reason we found it necessary to provide facilities for readily checking 
the levels of the channels in order that the sound-perspective at the 
time of reproduction would be the same as intended during the re- 
recording of the picture. A portable- type bridging input amplified 
volume-indicator having a range of 50 to +40 db (6-mw reference 
level) was provided for making all measurements. Multiple-track 
test-films and film-loops were used for making such measurements as 
level balance, gain-change characteristics, push-pull balance of the 
sound-track, and frequency response. Bridging jacks only were used 
at points in the circuits where routine measurements were to be made. 
Switches were so connected that resistance loads could be substituted 
for purpose of measurement. Vacuum-tubes having any bearing on 
the characteristics of the control-tone variable-gain section of the 
system were aged, balanced, and matched. This simplified the work 



July, 1942] ROAD-SHOWING FANTASIA 13 

for the field personnel in the routine maintenance of the equipment. 
Operating Features. The routine show-operating details were kept 
as near to standard theater practice as possible ; however, due to the 
use of a selsyn motor system and separate film reproducers, there did 
exist some difference in operating technic. There were three stations 
for the operating of the sound-control and motor systems. The 
motor controls for the selsyn system were operated by a sequence- 
switching arrangement that was quite foolproof. Suitable pilot-light 
indicating devices were employed for all control stations, and change- 
overs could be made from any station at any time. It was general 
operating practice to allow the selsyn motor on the picture machine 
and the multiple-track reproducer to remain "in lock" during the entire 
show, and because of this very little trouble was experienced from 
"out-of-sync" conditions. The power circuits were so designed that 
the entire system could be turned on by one switch, and during nor- 
mal operating times such was the practice. 

Manual switching was provided for monitoring the tone or pro- 
gram channels individually. This was fairly satisfactory with the 
exception that the volume range of the recording was too great for 
projection-room monitoring. With any reasonable adjustment for 
satisfactory high-level sounds it was impossible to hear the low-level 
sounds over the machine noise. Future equipment should be de- 
signed with a volume-compressor stage in the monitor amplifier and 
possible means for monitoring the combined channels. 

Shipping Facilities. All equipment was shipped from the factory 
in caravan packing units. Such packing facilities would no doubt 
have been satisfactory for the transfer of the equipment between 
installations. The weight of a complete Fantasound equipment was 
approximately 15,000 Ibs; it was packed in forty-five cases and re- 
quired one-half of a standard freight car space. 

The following information was obtained from eight Fantasound 
installations, and indicates the general conditions that were en- 
countered. Six of the installations required that a new or a larger 
capacity three-phase service be run to the projection room. The ma- 
jority of the six were new services, as no old services were available. 
In some theaters adequate single-phase power was not available in 
the projection room. Such additional power-line runs to the projec- 
tion rooms were always costly and time-consuming. In three of the 
theaters it was necessary to enlarge the projection room, as sufficient 
space was not available for all the equipment nor was there space 



14 W. E. GARITY AND W. JONES [j. S. M. p. E. 

nearby that could be used. This item made a large increase also in 
the installation cost. As a general rule the projection rooms en- 
countered were poorly arranged and too small for a first-class in- 
stallation of the entire equipment. It must be remembered, how- 
ever, that these theaters were not usually first-run motion picture 
houses, but were theaters that could be engaged for such a road-show 
project. 

In some of the earlier installations the right and left stage speakers 
were placed as far out to either side as conditions would permit. Pre- 
liminary tests indicated that this was undesirable, as there was an 
objectionable sudden movement of the sound when shifted from one 
loud speaker to another. The condition was corrected by moving 
the side speakers nearer the center by such an amount that a smooth 
transition occurred when the sound was shifted from one speaker to 
another. The correct separation of the theater stage speakers for 
obtaining a sound illusion similar to that obtained at the time of re- 
recording depends to a certain extent upon the general acoustic 
properties of the re-recording monitoring room and the location and 
spacing between the monitor speakers. Due to the fact that the 
Disney re-recording monitoring room is a 600-seat theater of average 
theater acoustic properties, it was more or less an easy matter to 
anticipate the final results. 

The normal undistorted audio-power output of the equipment was 
220 watts, which proved satisfactory for most theaters. In the 
Broadway Theater (New York) the power was increased to 400 watts 
and three additional loud speaker systems were added to the stage 
complement to handle the additional power. 

The music and the control-tone tracks for Fantasia were re-recorded 
with the idea that a certain volume-range could be used in the 
theater showing the picture. This volume-range as chosen, which 
consisted of a 40-db control-tone range and a 30-db range on the 
music tracks, was found to be greater than could be tolerated in the 
theater. It was general practice to use the high-level section of the 
music as the point at which the gain-controls were set for the correct 
level. If the low-level portions of the music were below the theater 
noise-level, the volume-range was reduced by changing the ratio of 
the control-tone level to the variable-gain amplifier output. The 
music was re-recorded with a one-to-one ratio; however, in some 
theaters it was necessary to use a ratio of eight to .five. This means 
of controlling the volume-range of sounds that have already been 



July, 1942] ROAD-SHOWING FANTASIA 15 

recorded was found to be very useful and necessary for the successful 
presentation of the picture. The best audience reaction to the high- 
level musical passages occurred when the level was at a certain value, 
which varied from theater to theater and was determined by trial and 
error. A decrease of 2 db in this level resulted in a decided "let- 
down" of audience reaction as the "thrill," or "punch" was lacking. 

Conclusions. The outstanding success of Fantasia in its limited 
number of runs with Fantasound has demonstrated the value of this 
means of increasing the dramatic value of a picture. 

There were three primary reasons for the discontinuance of the 
use of Fantasound: 

(1) The amount of equipment required and the time necessary to make the 
installation. 

(2) Because of the time element attractive theaters were not available to us, 
as the first-class houses in the various communities had established policies and 
the installation of the equipment would generally require darkening the house for 
a few days. 

(5) The advent of wartime conditions precluded the possibility of developing 
mobile units that would have lessened installation time and costs. 

(4) The variation in the regulations throughout the country, both as to operat- 
ing personnel and local ordinances, materially affected the operating and in- 
stallation costs. 

(5) Space factors of the projection room in particular were problems of major 
importance. 

We are convinced that, with greater simplification of equipment in 
keeping with the available space in the theater, the elimination of the 
separate selsyn sound-track reproducer, and the combining of the 
multiple-track on the composite print, future sound reproduction 
will employ multiple-track reproduction with automatic volume 
control, and, something that was not used in Fantasound, the auto- 
matic change of frequency-response with volume. We can only 
express our own opinions and the opinions of those who worked with 
this equipment; viz., having used the multiple-track system, no 
matter in what form, the ordinary sound-track reproduction is flat 
and dull by comparison. We can not say what the problems of 
original recording would be for the live-action producer. We can 
assume they will be many and various, but we are sure that with 
study and ingenuity they can be overcome, and the final results will 
be worth while. 



THE FUTURE OF FANTASOUND 

EDWARD H. PLUMB** 



Summary. A non-technical discussion of Fantasound from the musician's point 
of view. The use of Fantasound is reviewed as a basis for discussing ways in which 
it can be used in the future. 

Fantasound has been demonstrated to the public only in Walt 
Disney's Fantasia, but to accept or reject Fantasound on the basis 
of its use in that picture would be unjust. Fantasia is a remarkable 
showcase for an experiment in sound engineering because it uses 
music as a vital function of the picture. However, the dramatic 
effectiveness of Fantasound was limited by three conditions peculiar 
to this production. 

(1) During its actual picture footage Fantasia uses only music 
on the sound-track. This eliminates the possibility of placing and 
moving dialog or sound-effects in the multiple speaker system that 
Fantasound includes. Dialog and sound-effects are the "real" 
sounds of the movies with which the audience is thoroughly familiar. 
Because of this familiarity it is quite possible that the location of 
these sounds in the theater could be more easily registered than the 
placement of musical sounds. 

(2) The music that Fantasia interprets was conceived long before 
sound-film was available for use. The compositions were designed 
for concert performance and were so well designed for that medium 
that any orchestral changes made to improve reproduction greatly 
affected their basic character. 

(3) The original recording of the entire orchestral performance 
of Fantasia had been completed before it was known what dimen- 
sional effects would be available in the theater. It was thus im- 
possible to guess what method of recording would be most efficient 
for reproduction in Fantasound. 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received May 
1, 1942. 

** Music Department, Walt Disney Studio, Burbank, Calif. 

16 



THE FUTURE OF FANTASOUND 17 

This is in no sense to be interpreted as an apology for Fantasia or 
the methods used in it. It is merely a description of certain ob- 
stacles that would not be confronted in the usual feature. 

The future of Fantasound depends upon the efficiency with which 
the original sound material can be transferred to film and upon the 
dramatic effectiveness of the total result. These related factors 
dictate the future of Fantasound because they represent, respectively, 
the expenditure necessary and the expenditure warranted by box- 
office returns. 

Before suggesting a method of recording an orchestra that might 
be practicable for future productions in Fantasound it seems advis- 
able to describe briefly the method employed in Fantasia. During 
the original performance, each of six sound cameras recorded the 
close pick-up of a particular section of the orchestra. A seventh 
camera recorded a blend of these six close pick-ups, and an eighth 
recorded a distant pick-up of the entire orchestra. 

. In preparing the final re-recorded tracjc from this original material 
several weaknesses became apparent. Because of acoustical pick-up 
the separation between the six sections of the orchestra was merely 
relative. In the material on the woodwind channel, for instance, 
the woodwinds usually predominated, but material from other sec- 
tions of the orchestra was definitely present. Many times, because 
of differences in performance level, the material from adjacent sec- 
tions would be as loud as, or louder than, the woodwinds directly 
picked up. This lack of complete separation was not an insur- 
mountable obstacle in creating an artistic balance for ordinary re- 
production, but it greatly limited the dramatic use of orchestral 
colors in Fantasound. If we wished, for dramatic reasons, to have 
a horn call emanate from a point to the right of the screen, our pur- 
pose would be confused by hearing the same call, at a lower volume, on 
every other speaker in the theater. Greater separation in the original 
recording could have been achieved only by greater segregation of 
the sections or by moving the microphones closer to the individual 
instruments. To go any further than we had gone toward segrega- 
tion of sections or close pick-up would have impaired quality of 
performance in one case and recorded tone quality in the other. 
On the point of efficiency of the Fantasia recordings we must observe 
that only one-third of the material recorded on chosen performances 
was used in the final dubbing. The unused film contained sound 
that was too repetitious of other channels, too poor in quality, or, 



18 E. H. PLUMB [j. s. M. P. E. 

during long sections, too unimportant in the design of the composi- 
tion to help the total result. 

Since the completion of Fantasia we have recorded orchestral 
performances of five compositions for possible use in Fantasound. 
It is not likely that these can appear as productions for a long while, 
but the method that was used may provide a possible approach to 
future Fantasound projects. The recordings were much less expen- 
sive and, there is every reason to believe, can be much more effective 
dramatically than the Fantasia recordings. We concentrated upon 
the achievement of two qualities of Fantasound that seem to us to 
be important the illusion of "size," possible to attain by proper use 
of a multiple-speaker system, and recognizable placement of or- 
chestral colors important to the dramatic presentation of the picture. 

For the illusion of "size" or "spread," we used a three-channel 
recording set-up. Channel A was fed by a directional microphone 
far enough from the instrumentalists to cover the entire left half of 
the orchestra. Channel B recorded the right half of the orchestra. 
Channel C recorded a distant pick-up of the entire orchestra. This 
three-channel system recorded the "basic" tracks of the composition. 
It is important to note that in planning the material for these "basic" 
tracks any orchestral color or passage for which we might have special 
dramatic use was omitted from the performance. The recording of 
this special material will be described later. 

In reproduction over the Fantasound system this method of re- 
cording the basic tracks has great flexibility. To regain the natural 
spread of the orchestra, the A channel (left half of the orchestra) 
appears on the left stage speaker, the B channel (right half of the 
orchestra) appears on the right stage speaker, and the C channel 
(distant pick-up) appears on the center speaker. The distant pick- 
up appearing in the center adds an illusion of depth which is bene- 
ficial and also provides a more practical "cushion" for the solo in- 
struments or other special material that would normally appear in 
the center. The "panpot" (described by Garity and Hawkins in 
the August, 1941, JOURNAL) can execute practically any variation 
of this reproduction plan that could be demanded. Each track 
can appear on any one stage speaker, any two stage speakers in 
whatever balance desired, or on all three stage speakers in any bal- 
ance. The house speakers can be added to the left and right stage 
speakers in whatever set balances desired, or they can replace the 
left and right stage speakers so that sound comes only from left and 



July, 1942] THE FUTURE OF FANTASOUND 19 

right house and center stage (as in "Ave Maria" in Fantasia). 

In the recording of what I have termed special material material 
whose location it is important to register we employed the only 
method that assures absolute separation. The section of the basic 
track with which the special material is to synchronize is used as a 
playback on earphones available to conductor and instrumentalists. 
The physical difficulties of this method can be minimized by careful 
planning of the orchestration. It is usually possible to avoid the 
occurrence of the same melodic passage or rhythmic pattern in both 
the special and basic material. This makes synchronization less 
critical and also allows more freedom in performance of the special 
material. As advantages, the playback method offers complete 
control of the volume relationship between special and basic material ; 
complete freedom in locating or moving the -special material; and 
freedom to choose the pick-up, in recording the special material, 
that produces the finest quality in reproduction. 

As an example of the use of the playback method, in The Swan of 
Tuonela, by Sibelius, there is an English horn solo that is vitally 
important in the design of the composition. We knew that this 
English horn should be a principal actor in dramatizing the score. 
We had recorded the composition played by the complete string 
orchestra omitting, among other instruments, the English horn. 
We then recorded the English horn alone, using the performance by 
the strings for the playback. A relatively distant pick-up was used, 
which gave the tone of the English horn brilliance, but also lent a 
feeling of mystery in character with the subject. Because of the 
complete separation achieved it is possible to submerge the solo in 
the rest of the orchestra or to make the solo stand out in a clear relief 
physically impossible to attain in concert performance. The solo 
can locate as its source one of the three stage speakers or, by balanc- 
ing its volume between two speakers, can seem to locate a definite 
point between them. The solo can come from the left or right unit 
of house speakers without the stage speakers or, if power or diffusion 
are desired, can come from every speaker in the theater. The solo 
can move in such a way that it seems to follow the pattern of a pic- 
torial effect; it can change from offstage to onstage; or it can change 
its source, by a smooth, irregular movement of the panpot dial, so 
that it seems to float through the theater. I have mentioned a 
single composition and only a few of the effects possible. However, 
it is clear that the restrictions offered by this tentative method are 



20 E. H. PLUMB [j. s. M P. E. 

infinitely less than those offered by the method used for Fantasia. 
(The Fantasia score contained only one example of complete separa- 
tion the solo voice and chorus of "Ave Maria" were recorded by 
the playback method to an orchestral accompaniment recorded a 
year and a half before. The vocal performance of "Ave Maria" 
was the last material to be recorded for Fantasia, and we were able 
to use everything Fantasound had to offer. It is interesting to note 
that for many of those in the audiences at least in New York and 
Los Angeles Fantasound was "turned on" only for "Ave Maria.") 

The advantages of volume range are probably more obvious than 
the advantages of other features of Fantasound. To be able to use 
the upper volume range without distortion and the lower range 
without submerging the tone in ground-noise has been the dream of 
every dramatically minded sound-director since the advent of sound 
reproduction. Experience shows us, however, that this greatly 
extended volume range still has important natural limits. If sound 
is reproduced so low that it is unintelligible or so high that it causes 
physical discomfort, there must be adequate dramatic reason. 
Either extreme is likely to irritate. 

Dialog and sound-effects, as material for use in Fantasound, have 
one decided advantage over music. They do not have to be recorded 
differently from the customary recording of ordinary sound. Their 
placement, movement, and extended volume range are all accom- 
plished after they are normally put on the film. 

Dialog is the only sound medium in whose reception the audience 
has been well rehearsed. The average member of the audience has 
heard the sounds that the screen sound-effects imitate, but he does 
not ordinarily analyze their character or location with any great 
care. He has listened to music but, perhaps wisely, he does not 
bother himself with the details of its complex pattern. In the recep- 
tion of speech, however, he has trained himself to register, in great 
detail, character, pitch, volume, and location. Location of sound- 
source is an unconscious function of his daily group conversation, 
group work, and group play. It is reasonable to expect, then, that 
when dialog placement has dramatic meaning it will be efficiently 
received by the audience at least, more efficiently received than 
the placement of sound-effects or music. Because of the visual 
limitations of the screen, dialog, in Fantasound as in ordinary repro- 
duction, comes normally from the center of the stage. For this 
purpose the center stage speaker is adequate. Because the ear is 
critical of voice placement, however, it is not far-fetched to attempt 



July, 1942] THE FUTURE OF FANTASOUND 21 

the location of characters by changing the speaker source. If an 
actor appears in the area at the extreme left of the projected frame, 
or if the implied location is slightly to the left of the projected frame, 
placement of the voice on the left stage speaker supports the illusion. 
Such use of the three stage speakers creates the possibility of dialog 
between extreme left and extreme right or between center and either 
side without greater sacrifice of intelligibility than would exist in 
dramatic productions on the stage. Obviously the device could be 
over-used to the point of annoyance, and should be limited to dra- 
matic situations that are definitely improved by the illusion. In 
the treatment of off-stage voices the house speakers could be used 
to advantage. When a voice, or a group of voices, comes from the 
left or right unit of house speakers, an effect of reverberation is added 
to the original recording. The loss in intelligibility and in point- 
source definition could have dramatic value because they imitate 
these same losses in the reception of real sounds from a distance. 

Fantasound is able to make its greatest contribution in combining 
dialog, music, and sound-effects. In ordinary reproduction one of 
these three mediums must, with rare exceptions, be dominant while 
the other two are sacrificed. In Fantasound it is possible to follow 
the continuity of the dialog clearly and still receive the full emotional 
impact of the music, or the dramatic realism of atmospheric sound- 
effects. As a possible use in the theater, consider that the center 
stage speaker would be saved exclusively for on-stage sound dialog, 
music performed on the screen, or realistic sound-effects. The 
house speakers and, at a lower level, the side stage speakers would 
project music or general sound-effects at a level natural for them. 
As long as the music or effects are pertinent to the story being por- 
trayed they will not distract and would not cause the dialog to be- 
come unintelligible. This physical separation of sound-tracks also 
reduces to a minimum the unpleasant phenomenon produced when 
a well-modulated track is "pinched." 

If these comments seem to wander it may be because Fantasound 
is at the wandering stage of its development. We have the tools and 
we have not decided what we intend to build with them. These 
tools may not be available in the theater "for the duration," but 
this might be an excellent period during which to develop a practi- 
cable, effective plan for using them. It is within the power of Fanta- 
sound, as an idea, to revitalize the industry. This power, however, 
can not be fully developed until script, direction, music, and recording 
are planned with Fantasound as an organic function. 



MOBILE TELEVISION EQUIPMENT 5 



R. L. CAMPBELL, R. E. KESSLER, R. E. RUTHERFORD, AND 
K. V. LANDSBERG** 



Summary. While portability is a necessary requirement for outside pick-up 
equipment, several advantages result when portability is carried into the studio. 
To equip a studio of adequate size with fixed equipment for operation of several cam- 
eras involves considerable time and expenditure. However, with portable studio 
equipment, the entire equipment installation can be located to suit studio needs, as 
well as moved to different studios or outside locations. , 

The dolly type equipment is described in some detail and systems for program con- 
trol are discussed. Some of the design features discussed are portable and flexible 
synchronizing equipment; electronic view finders; oscilloscope monitors; and other 
operating facilities. 

In the course of the development of television equipment, many of 
the improvements and simplifications resulting in better apparatus 
from the standpoint of performance and convenience of use are really 
the applications of ideas developed in allied fields that have been 
transferred to meet television design requirements. It may also be 
said that television equipment design must follow, to some extent, the 
established precedents and engineering practices (e. g., radio broad- 
casting equipment). When the precedent is followed too closely, 
however, difficulties are likely to appear in operation and maintenance 
because of the inherent complexity of the television system. In 
sound broadcasting there is only one electrical signal comprising the 
intelligence to be transmitted. In television there are five separate 
electrical waves (sometimes more depending upon the system em- 
ployed) which are combined and transmitted simultaneously to be 
used at the receiver in order to reproduce the picture. To make up 
this composite television signal wave, several electrical wave-forms 
not appearing in the final signal must be generated in order to obtain 
the television system operation as we know it today. From this it 
can be seen that the operation of a television camera is by no means as 

* Presented at the 1941 Fall Meeting at New York, N. Y.; received October 
20, 1941. 

** Allen B. DuMont Laboratories, Passaic, N. J. 

22 






MOBILE TELEVISION EQUIPMENT 23 

simple an operation as setting up and operating a microphone for 
sound work. 

With the above in mind, the purpose of this paper is to describe a 
type of television camera equipment designed both for studio and out- 
door use with respect to its function in a television operating plant. 
Particular components of the system to be described are (1) mobile 
camera control dolly ; (2) electronic view-finding system ; (3) flexible 
synchronizing equipment; (4) sweep-driven control apparatus; (5) 
interchangeability of units; (6) cross-control of camera dollies; and 
other operating features. Particular reference will be made to me- 
chanical considerations as well as some novel electrical features used 
in the equipment. 

One application of this equipment would be for broadcast studio 
operation. The economic factors involved in equipping a studio 
solely for television operation are likely to be out of proportion to the 
anticipated return on the investment in the case of most broadcasting 
stations or other operating enterprises. Using the studio-type port- 
able equipment, television programs can be presented with a minimum 
of installation difficulties. The cameras and camera-control equip- 
ment are merely rolled into the studio (together with adequate port- 
able lighting fixtures) and the show is on. In the case of remote work, 
special events, etc., the same equipment can be wheeled into a small 
truck, and unloaded and quickly set up for operation into a video line 
or relay channel. 

A familiar and important requirement of portable equipment is 
weight. Considering the number of complex circuits involved in a 
television system, it can be seen that this problem is much more se- 
vere than in the case of equipment for remote sound work. Consid- 
erably more apparatus is involved, and the question that immediately 
arises is, "Shall we have a few heavy units or shall we have several 
small, light-weight units?" In this equipment the latter was chosen 
for the following reasons : 

(1) The most logical electrical arrangement was to split the system into 
several units according to their functions. 

(2) Standard mechanical chassis arrangements could be adopted for ease of 
manufacture. 

(5) Servicing of all units was to be as convenient as possible. 

(4) No unit should be a two-man job to carry. 

(5) Future improvements can be added by replacing a unit at a time if de- 
sirable. 



24 CAMPBELL, KESSLER, RUTHERFORD, LANDSBERG [J. S. M. P. E. 

(6) Television cameras using different types of pick-up tubes may be used on 
the same equipment chains. 

The camera and corresponding control equipment are arranged to 
operate in single or dual chains. In the case of a single chain, this 
equipment is divided into units as follows : 

(1) Synchronizing generator (9) Camera monitor 

(2) Blanking sweep and power unit (10) Camera monitor power supply 

(3) Camera (11) Camera control power supply 

(4) Camera power supply (12) Line amplifier 

(5) Electronic view.-finder (13) Line amplifier power supply 

(6) View-finder supply (14) Line monitor 

(7) Camera control (15) Line monitor supply 

(8) Shading generator* 

For a dual chain, the equipment required is : 

(1) Synchronizing generator 1 (9) Camera monitor 2 

(2) Blanking sweep and (10) Camera monitor supply 2 

power unit 1 (11) Camera control power 

(3) Camera 2 supply 1 

(4) Camera power supply 2 (12) Line amplifier 1 

(5) Electronic view-finder 2 (13) Line amplifier power 

(6) View-finder supply 2 supply 1 

(7) Camera control 2 (14) Line monitor 1 

(8) Shading generator** 2 (15) Line monitor supply 1 

In Fig. 1 is shown the apparatus outlined above arranged for dual 
chain operation. On the camera-control dolly are the synchronizing 
generator, power units, camera-control units, monitors, and line equip- 
ment. With each camera connected to the main equipment dolly is 
the auxiliary camera power-unit and the view-finding apparatus. 
This assembly is then connected back to the camera-control dolly by 
means of the camera cable, interlocked a-c power cable, and view- 
finder video cable. 

For studio use the camera equipment proper is sometimes mounted 
on a studio platform dolly having a pedestal arranged to take the 
Akeley gyro tripod head shown in the figure. The camera dolly plat- 
form supports the camera equipment and the cameraman, and it can 
be moved about the studio for camera "dolly" action shots. 

Synchronizing Generator. The synchronizing generator used in this 
equipment is of the flexible fully electronic type and generates the 
DuMont synchronous wave (Fig. 4) . The generator can be operated 

* For use in conjunction with iconoscope cameras. 
** For use in conjunction with iconoscope cameras. 



July, 1942] 



MOBILE TELEVISION EQUIPMENT 



25 



on any of the standards listed below, and can be easily converted to 
other standards that may be desirable without affecting the standard 
chosen for regular operation. 



Lines/frame 

441** 
525* 
625** 
343 f 
441 j 



Fields/second 

60 
60 
30 

120 

120 



Interlace 

2:1 
2:1 
2:1 
2:1 
2:1 



The synchronizing system may be switched to any one of the above 
standards by means of a single wave switch and a few simple adjust- 
ments. 




FIG. 1. Dual camera chain equipment. 

The complete generator is housed in two units, viz., the synchro- 
nizing generator unit and the blanking sweep and power unit. Fig. 2 
shows the front panel of the synchronizing generator unit with the 
cover removed. At the top of the unit is a monitor CRO (cathode- 
ray oscillograph) which is connected to all circuits provided with 
front panel adjustments. This CRO is of the "automatic" type; 
that is, the timing axis is automatically synchronized to the signal 
selected by the monitoring selector switch by means of an additional 

* F. C. C. (49851) "Television Report," May 3, 1941; also Donald G. Fink, 
National Television System Committee, Doc. No. 505L-200M1. 
** Experimental Standards, 
t Color Standards. 



26 CAMPBELL, KESSLER, RUTHERFORD, LANDSBERG [J. S. M. P. E. 

deck on the selector switch. Because of the many complex circuits 
involved in a synchronizing generator, and because it is desirable 
during operation to check the performance of the entire instrument 











FIG. 2. Synchronizing generator with front cover 
removed. 

without shutting down or throwing it out of adjustment, this monitor 
CRO is considered essential. 

Fig. 3 is a block diagram of the synchronizing system employed in 




LINE AMPLIFIER 




LINE MONITOR 


1 



FIG. 3. Diagram of scanning and synchronizing system. 

the equipment. The synchronizing generator can be divided into 
units according to the function of the various circuits. 

Unit No. 1 (1} Monitor CRO 

(2} Frequency divider circuit 



July, 1942] MOBILE TELEVISION EQUIPMENT 27 

(3) Composite synch wave generator 

Unit No. 2 (4) Composite blanking 

(5) Master sweep generator 

(6) Power supply 

The monitor CRO has been explained above. The frequency divider 
unit consists of transformer-coupled relaxation oscillators arranged 
to divide in accordance with the line and frame scanning standards 
selected. The switch to different standards is accomplished by means 
of a multiple deck wave switch, connected to the oscillator and asso- 
ciated circuits, whereby the optimal circuit constants are selected for 
operation on the scanning standard chosen. 

Vertical Synch f\j\se 

f Interval t 

< 




H- Horirontal Scanmnq Interva I 
V' Vertical Scanmnq Interval 

H Synch 
Pulse Interval c 
.OOH [ 



A/TY\AA_/U\}JWAT\T\P 

Expanded View of Section C-D K+*f f 

e>f Vfertical Pi/lit. Interval Microcond Scale 

V4*w Only 



FIG. 4. DuMont synchronizing signal. 

The composite synchronizing signal generator circuit develops the 
synchronizing wave as shown in Fig. 4. Use of this type of signal 
makes it possible to minimize operating difficulties in the field so far 
as synchronizing generator performance is concerned. This is prin- 
cipally due to the fact that the composite synch signal consists of two 
signals that are relatively simple to generate. Furthermore, im- 
proved vertical synchronizing performance is attained at the re- 
ceiver.* In the composite synch signal generator is the shaping cir- 
cuit for horizontal pulses, the high-frequency carrier pulse generator 
for the field pulses, and the mixing and output circuits. 

The blanking, sweep, and power unit contains the circuits indi- 
cated in its name. Power for all circuits in the generator is supplied 

* National Television System Committee, Doc. No. 325R-200D31. 



28 



CAMPBELL, KESSLER, RUTHERFORD, LANDSBERG [J. S. M. P. E. 



from this unit by means of a well filtered, regulated supply. From 
the generator unit, driving pulses are fed to the sweep generators 
which control the scanning circuits on the cameras, monitors, and 
shading generators. 

Horizontal and vertical blanking voltages are derived from the re- 
spective sweep signal generators and shaped in the blanking generator 
circuit. They are next mixed to form a composite blanking wave 
which is fed to the camera-control unit. 



CAMERA 




CAMERA CONTROL 












1 


To L.n, 






SHADING GENERATOR 


J 












LINE AMPLIFIER 










| ^VIDEO AMPLIFIER P | 


CAMERA 




CAMERA CONTROL 












J 








SHADING GENERATOR 







FIG. 5. Diagram of video system. 

Low-impedance outputs are provided in the synchronizing gener- 
ator unit to feed a single or dual camera chain with the following sig- 
nals: 



(1} Horizontal sweep 

(2) Vertical sweep 

(5) Composite blanking 

(4) Composite synch 

By means of the synch distribution unit, several camera chains may 
be controlled from one generator if desired. For normal operation 
on dual chain, and with reasonable cable lengths, the synch distribu- 
tion unit can be eliminated. 

Video System. Fig. 5 shows the video system employed in a dual 
chain. The video signal generated in the iconoscope output resistor 
is fed to the preamplifier in the camera, where correction for capaci- 
tance of the iconoscope output circuit is accomplished by means of a 
peaking stage in this amplifier. A cathode follower output stage on 
the preamplifier feeds through the main cable to the camera-control 
amplifier, which will be described later. 



July, 1942] 



MOBILE TELEVISION EQUIPMENT 



29 



Camera. Fig. 6 shows the camera equipment. In the camera are 
the video preamplifier (Fig. 7), camera sweep circuits, a type 1850 
iconoscope, camera blanking circuits, and protective circuits. Power 
for these circuits is fed from a separate cable from the camera power 
unit. The amount of power dissipated in the camera itself is such 
that the heat generated by the tubes would be excessive, especially 
when used in a "hot" studio or out in the sun. Therefore, it has 
been found desirable to isolate 
those tubes generating most of 
the heat and place them upon a 
deck on the exterior of the 
camera. The lens mechanism is 
operated by means of a handle at 
the side, and provisions are made 
for interchanging lenses in the 
approximate range of 6*/2 inches 
//2.5 to 16 inches //3.5. 

Camera Control. In the cam- 
era control unit are the following 
circuits : 

(a) Video blanking amplifier 
(6) Camera horizontal sweep con- 
trol and keystoning circuit 

(c) Camera vertical sweep control 

circuit 

(d) Pedestal control 

(e) Iconoscope beam control 
(/) Iconoscope rim light control 
(g) Monitor and view-finder video 

supply circuits. 




FIG. 6. 



Camera equipment (Icono- 
scope). 



The camera cable terminates in 
the r.ear of this unit, and all 

signals feeding the camera pass through the camera control unit. 
(Note : The video signal to the view-finder is fed over a separate small 
co-axial cable.) A test-circuit for checking the plate currents of ampli- 
fier tubes in the camera control is connected by means of a switch to a 
meter on the front panel. The camera video amplifier comprises 
five stages and two blanking clippers. 

Of interest in the camera control unit are the blanking circuit and 
the pedestal control circuit. The former utilizes a low-impedance 
diode limiter for clipping the blanking pedestal after mixing, and be- 



30 



CAMPBELL, KESSLER, RUTHERFORD, LANDSBERG [J. S. M. P. E. 



yond this point in the amplifier is the pedestal control which is a simi- 
lar diode circuit, but has a variable d-c bias control for adjusting the 
amplitude of the pedestal in accordance with lighting conditions. 

The video output circuit of the camera control consists of a high- 
level cathode loaded stage which feeds the line amplifier and a low- 
level cathode loaded stage for feeding the monitor, view-finder, and 
shading generator CRO. Fig. 8 is an interior view of the camera con- 
trol on the wiring side. Power for the camera-control unit is ob- 
tained from a separate, regulated supply to which the camera power 
and view-finder power units are interlocked. 

View-Finder. In motion picture production, probably the most 
important technician is the cameraman. His successes or failures 




FIG. < . Camera preamplifier. 

are very probably due to his ability, before the shot is taken, to visu- 
alize how the particular scene will appear when projected on the 
screen. By means of the electronic view-finder, the television cam- 
eraman has an instantaneously developed picture before him at all 
times. View-finding by means of matched lenses is an alternate 
method by which the cameraman can monitor his work. This 
method is expensive, however, and does not lend itself readily to quick 
interchangeability of lenses, sometimes required during programs. 
For these reasons the electronic method of view-finding was chosen. 
Besides being able to determine the pictorial value of the scene before 
the camera, the electronic view-finder is used as the focusing monitor. 
Thus, the cameraman can adjust the optical focusing instantaneously, 
and since he is in control of the camera, he can anticipate to some ex- 



July, 1942] 



MOBILE TELEVISION EQUIPMENT 



31 



tent the position of the focusing handle and thus maintain the optical 
focus at all times. As an auxiliary to the electronic view-finder, a 
framing device of some variety or other, or a Mitchell finder, is some- 
times attached to the camera for the purpose of providing finding 
facilities outside the field taken in by the camera. 

The electrical arrangement of the view-finder is as follows : A high- 
intensity 5-inch electrostatic- type cathode-ray tube is sweep-driven 
from signals to the camera. The sweep voltages are applied to plates 
of the cathode-ray tube by means of amplifiers located within the 
view-finder unit. The video signals fed to this unit are tapped off a 




FIG. 8. Camera control unit, wiring side. 

monitor line in the camera control and fed to a video amplifier in the 
view-finder unit. Power and control circuits located in the view- 
finder supply-unit are fed to the view-finder by means of an inter- 
connecting cable. (Controls are provided on the view-finder unit for 
maintaining the adjustments of brightness, contrast, and electrical 
focus, similar to those employed in television receivers.) Figs. 9 and 
10 show the internal arrangements of the view-finder and view-finder 
supply-units, respectively. 

Shading Generator. The shading control generator is a separate 
unit in the equipment and is used only in conjunction with iconoscope 



32 



CAMPBELL, KESSLER, RUTHERFORD, LANDSBERG [J. S. M. P. E. 



cameras. The shading signals are derived from the horizontal and 
vertical master sweep signals from the synchronizing generator. 




FIG. 9. View-finder interior view. 




FIG. 10. View-finder supply, interior view. 



From these sweep 
ated in this unit : 



signals the following shading voltages are gener- 



(a) Horizontal saw-tooth 

(&) Horizontal parabola 

(c~) Horizontal sine 

(d) Vertical saw-tooth 

(e) Vertical parabola 
(/) Vertical sine 



July, 1942] MOBILE TELEVISION EQUIPMENT 33 

These signals can be controlled both in amplitude and phase so that 
many varieties of composite shading voltage can be obtained. These 
signals are mixed in a common amplifier whose output is fed into the 
iconoscope output circuit by means of a line in the camera cable. In 
the shading generator are the following circuits. 

(a) Shading generation, mixing, and output circuits 

(&) Shading CRO 

(c) Internal power unit 

Video from the corresponding 
camera control is fed to the 
shading generator CRO in order 
to monitor the shading signals. 
The time axis on this CRO is 
driven from either the horizontal 
or vertical sweep depending upon 
the setting of a switch on the 
front panel. Thus, the operator 
selects the line-frequency sweep 
for checking horizontal shading, 
and the field-frequency sweep for 
checking vertical shading. A 
regulated supply is used to power 
all the units in this circuit. Fig. 
1 1 shows the shading generator. 

Camera Monitor. On each 
camera chain is a monitor unit 

connected by cable to the camera FIG. 11. Shading generator, 

control corresponding to the 

camera being operated. This monitor is usually placed directly on top 
of the camera control or shading generator for the convenience of 
the operator. The camera monitor is powered from the camera 
monitor supply by means of an interconnecting cable. Since elec- 
trically the camera monitor is identical with the view-finder, it need 
not be described further here. Fig. 12 shows a camera monitor unit 
and Fig. 13 the monitoring system in general. 

Line Amplifier. Normally, the camera-control units generate 
video signals at sufficient level for feeding monitor lines and control- 
ing a camera chain as outlined above. However, the signals from the 
two cameras must be selected or mixed, as the case may be, and then 




34 CAMPBELL, KESSLER, RUTHERFORD, LANDSBERG [J. S. M. P. E. 



mixed with the synchronizing signal to form the composite television 
signal. This is accomplished in the line amplifier, which contains the 
following circuits : 

(a) Video switching unit 

(6) Synch mixing amplifier 

(c) Main output stage 

(d) Four auxiliary output stages 

(e) Monitor CRO 

Push-button switching of cameras is accomplished in the switching 
unit by selecting one or the other of camera-control video signals. 
The composite synch signal from the synchronizing generator is fed 

to the line amplifier, as well as 
the two video signals. Just be- 
fore the output stage, a mixing 
circuit is provided to introduce 
the synch signal with the video. 
A synch gain control is provided 
for maintaining the proper per- 
centage of synch signal to video. 
In the event that separate synch 
transmission is used, this signal is 
cut at this point and fed directly 
from the generator to the trans- 
mitter or relay apparatus. Fig. 
13 shows the line amplifier unit. 
The main output stage of the 
line amplifier is a heavy-duty 
cathode follower stage which 

normally feeds a 75-ohm line at an approximate level of 6 volts. 
In addition to this stage, three low-level stages are provided for 
75-ohm monitor lines, such as program directors, auxiliaries, and 
local monitor. The monitor CRO is for the purpose of monitoring 
the signal out on the various lines. The video signal applied to the 
CRO is normally connected to the main output line. However, 
by means of a plug-in arrangement at the back, this CRO can be 
used to check all input and output terminals on the unit. Power 
for the line-amplifier unit (excepting CRO power, which is a built- 
in unit) is obtained from a separate supply which is identical to that 
used for powering the camera-control unity. Fig. 14 shows the tube 
side of the line amplifier. 




FIG. 12. Camera monitor unit. 



July, 1942] 



MOBILE TELEVISION EQUIPMENT 



35 



Line Monitor. The line monitor unit is used for checking the signal 
selected by the switching unit (Fig. 13). In addition to monitoring 
the video signal fed out on the line, this unit serves also to monitor 
the synchronizing performance of the entire system. The viewing 
unit of the monitor is identical with the camera monitor previously 
mentioned, with the exception of the driven sweeps, and is powered 
from a supply unit also identical with the camera monitor supply. In 
addition to this supply, however, is a synchronizing wave from the 
composite scanning unit for separating the synchronizing wave from 
the composite signal and applying it to the horizontal and vertical 
sweep oscillators of this monitor in the same manner as in typical 




CAMERA 
MONITOR 



CAMERA 
CONTROL 




V 


SHADING 
GENERATOR 




1 SHADING C R 


CAMERA 


Idta | 




SUPPLY 


S.eep 




SYNCH 
GENERATOR 





LINE 
MONITOR 




To TranmlHr 



FIG. 13. Diagram of monitoring system. 



home television receivers. This line monitor, while intended prima- 
rily for operation with the DuMont synchronizing signal, is arranged 
to operate on synchronizing signals having rectangular field pulses as 
well as those of the radio-frequency type. 

Control Dolly and Operation. The camera-control dolly is alight- 
weight frame on 10-inch pneumatic wheels occupying a floor space of 
64 X 28 Y 2 inches for a dual chain. The height of the control desk 
is 30 inches, and the operating desk slides into the unit when not in 
use. Single or dual equipment is controlled from the camera-control 
dolly by the camera-control operator. He has control over the elec- 
trical performance of the video system, including -the synchronizing 
generator. Each camera is operated by a cameraman who, with the 
aid of the electric view-finder, follows the action, maintains the focus, 



36 CAMPBELL, KESSLER, RUTHERFORD, LANDSBERG 

and is in general control of the pictorial value of the subject matter 
being picked up by his camera. There are provisions for interphone 
connections by which this operator is in communication with the 
two cameramen and also with the terminal point to which the video 
signal is being supplied. A sound program control-unit is sometimes 
mounted on the camera-control dolly. When sound facilities are con- 
trolled here, some of the duties of the video control operator can be 
taken over by the sound man. 




FIG. 14. Line amplifier, tube side. 

BIBLIOGRAPHY 

1 ZWORYKIN, V. K., AND MORTON, G. A.: "Television," John Wiley and Sons 
(New York), 1940. 

2 FINK, D. G. : "Principles of Television Engineering," McGraw-Hil1\Book Co. 
(New York), 1940. 

3 ENGSTROM, E. W.: "An Experimental Television System, Part I," Proc. 
IRE, 22 (Nov., 1934), p. 1241. 

4 WILSON, J. C. : "Television Engineering," Pitman & Sons (London), 1937. 

5 BEERS, G. L., SCHADE, O. H., AND SHELBY, R. E. : "Portable Television 
Equipment," /. Soc. Mot. Pict. Eng., XXXV (Oct., 1940), p. 327. 

6 CASTELLANI, A.: "II Sincronismo in Televisione," Estratto delta rivista, Radio 
Industria, No. 23, Luglio, 1936 (Milano). 

7 CAMPBELL, R. L.: "Television Control Equipment for Film Transmission," 
J. Soc. Mot. Pict. Eng., XXXIII (Dec., 1939), p. 677. 

8 GOLDSMITH, T. T., CAMPBELL, R. L., AND STANTON, S. W.: "A New Method 
of Synchronization for Television Systems," J. Soc. Mot. Pict. Eng., XXXV 
(Sept., 1940), p. 254. 



THE APPLICATION OF POTENTIOMETRIC METHODS 
TO DEVELOPER ANALYSIS* 



JOHN G. STOTT** 

Summary. Potentiometric titration methods are applied to routine developer 
analyses in order to simplify and speed up the operation and to minimize the human 
error arising from judgment of color change end points, etc. A brief theoretical treat- 
ment of potentiometric titrations is included, and new tests for elon, hydroquinone, 
and carbonate are outlined. Previously published methods for bromide and sulfite 
are also included. Detailed procedure outlines are included along with a discussion 
of the problem of pH vs. the alkali content of a developer. A glossary showing step- 
wise procedure operations required to accomplish the analyses has been compiled along 
with a complete equipment and chemical reagent list. The precision of the methods 
is evaluated by a table showing analysis data on carefully mixed known developers. 

In recent years the literature of photographic technology has 
yielded many schemes and procedures relative to the quantitative 
chemical analysis of photographic solutions. Many of these sugges- 
tions have dealt with but one or two of the common constituents of 
photographic solutions, particularly in the studies on developers, 
whereas a complete quantitative chemical analysis giving accurate 
data on all of the important constituents is essential in order to 
evaluate the actual photographic function of the developer. While 
all these contributions have been of value, it has been difficult for 
the motion picture laboratory chemist to segregate this maze of data 
and to arrive at a working procedure that will lead to rapid and con- 
sistently accurate results in the routine analysis of photographic de- 
velopers. 

The first corhplete working procedure for MQ developer analysis 
was published by Evans and Hanson 1 in 1939. The need for further 
clarification and extension to more general types of solutions was 
realized by R. B. Atkinson and V. C. Shaner, co-authors of 
"Chemical Analysis of Photographic Developers and Fixing Baths" 2 
published in 1940 and based, upon a careful study of the literature as 

* Presented at the 1942 Spring Meeting at Hollywood, Calif.; received April 
15, 1942. 

** Eastman Kodak Company, New York, N. Y. 

37 



38 J. G. STOTT [j. s. M. P. E. 

well as on their own work. The working procedures outlined call for 
a minimum of equipment and technical skill and give accurate and 
rapid results. 

With this information at his disposal, it is possible for the motion 
picture laboratory chemist to run complete chemical analyses on 
photographic developers with sufficient speed that the data obtained 
can be of immense value in production processing. 

It is the purpose of this report to construct a procedure of analysis 
such that all the more important constituents of an MQ developer may 
be determined by the application of one primary method of end point 
evaluation, the only variations from this standard procedure being 
in pretreatment of the developer solutions and in titrating reagents 
used. This is accomplished by the application of potentiometric 
methods to end point determinations. Thus the entire ' 'heart" of 
these analysis methods is some type of sensitive potential measuring 
device; without this instrument these methods are useless. All the 
work of this paper has been done using a Beckman pH Meter, Labora- 
tory Model G, which is so constructed that it can be instantly con- 
verted from a H-measuring device to a potential-measuring device 
with a range of - 1300 to +1300 millivolts. 

THEORETICAL TREATMENT 

Since these analysis methods depend entirely upon potentiometric 
methods, it will be desirable to outline briefly the theory behind the 
phenomenon in order to understand more clearly what is happening 
during the course of a potentiometric titration. 

When a metal is placed in a solution of its ions, such as a silver 
electrode in a solution of silver nitrate, an equilibrium is set up be- 
tween the metal and its ions in the solution that can best be repre- 
sented by the following equation: 

Ag + Ag+ + . ie 

silver silver electrode 

metal ion transfer 

A potential difference exists between this silver electrode and the 
solution of silver ions, the magnitude of the potential difference 
depending upon the concentration of silver ions. This silver elec- 
trode potential can be measured if a reference electrode is placed in 
the solution and connected to the silver electrode through a potentio- 
meter set-up. The reference electrode must be one that has a known 



July, 1942] 



POTENTIOMETRIC METHODS 



39 



potential and does not affect the reaction at the silver electrode. 
Such a standard electrode is the saturated calomel electrode which 
maintains a constant potential in respect to the solution regardless of 
the other electrode in the solution or the ions in the solution itself. 

Suppose that we are interested in determining the bromide concen- 
tration of a solution. A silver electrode and a saturated calomel 
electrode are placed in the pretreated solution, and the leads from the 
electrodes are connected to the potential measuring device. The 
potential of the silver electrode is then measured during titration with 

























1 


PICA 


RR 


3 MID 


1 DETEfiil 


"1 


























SIN( 
tfS-G 


STD 
A LOW 


AG 
LL I 


KOsWITH} 
LprYBni 


<^ 


R 






























































/" 




































/ 


















o 






































i 






































z 


















- 


-- 




VALE 


NCE 














PO'N 




< 
H 






































u 

p 




























































































^s 


7 




























- 


. - 


^ - - 


, 




























*** 


" 














































ML OF STD A 


NO 




- 















FIG. 1. Typical bromide determination. 

a standard silver nitrate, plotting a curve of the measured potential 
vs. the units of silver nitrate added. 

Upon addition of the first portion of silver nitrate to the solution 
containing bromide, nearly all the silver is removed from the solution 
as solid silver bromide. A small amount of silver ion remaining in 
solution in equilibrium with the silver bromide determines the po- 
tential of the silver electrode. A second addition of silver nitrate 
results in a further precipitation of silver bromide ; and since bromide 
ions are still present in excess, the amount of silver ion in solution is 
still the small amount in equilibrium with silver bromide, increased 
slightly due to the decreased bromide concentration. Since the 
change in silver ion concentration is very small, the potential change 



40 J. G. STOTT [j. s. M. P. E. 

is also small. However, when the bromide concentration becomes 
small, that is, when we approach the end point of the titration, the 
addition of the same increment of silver nitrate causes a much greater 
change in the silver ion concentration and the potential changes are 
greater, until at the end point we obtain the maximum slope in the 
plot of potential vs. silver nitrate. Such a curve is shown in Fig. 1. 
The end point of the titration is the point of maximum slope or the 
midpoint of the straight-line portion of the vertical part of the curve. 
The last portion of the curve represents the change in potential as 
the silver ion is increased, but since each addition increases the con- 
centration by a lesser increment than the preceding one the slope be- 
comes less. 

This type of reaction involving the precipitation of the constituent 
to be determined is but one of the types of reactions that may be 
studied by this method. Oxidation-reduction reactions may also be 
studied by measuring the change in the concentration ratio of the 
oxidized and reduced form of a substance using an inert electrode. 
Such a reaction is illustrated by the titration of an oxidation agent, 
such as iodine, with a reducing agent such as hydroquinone. In this 
titration the reaction of the oxidant may be expressed as follows : 

I 2 <= 21- 2e 

iodine iodide electron 

ions transfer 

The potential changes in the solution are due to the changing ratio 
of free iodine to iodide ions, and the rate of change of potential with 
added hydroquinone will follow a course similar to that in the silver 
nitrate-bromide system. 

Before a given substance can be determined by the method out- 
lined above it must be certain that interfering substances have been 
removed. This pretreatment of solutions prior to titration will be 
described in detail in the procedure outlines for the analysis of each 
constituent. 

This treatment of the theory underlying potentiometric titrations 
is merely an outline, and the reader is referred to texts on the subject 
for a more complete treatment of the subject. 3 

PROCEDURES 

These procedure outlines will deal with the actual operations re- 
quired in pretreatment of solutions prior to titration, along with a 
brief explanation as to the reason for carrying out these operations. 



July, 1942] POTENTIOMETRIC METHODS 41 

All the titrations will be carried out in a similar manner by determin- 
ing the potential of the unknown solution after each addition of a 
unit volume of reagent, and by plotting the potential in millivolts vs. 
the volume of reagent added. When the final titration curve has 
been drawn, the equivalence point of the titration is located as 
previously described, and a simple mathematical calculation will give 
the final analytical result. When further experience has been 
obtained in conducting potentiometric titrations, the need for plotting 
the titration curves in all the determinations will be eliminated since 
violent fluctuations of the potentiometer needle begin to occur near 
the equivalence point. Then the actual location of the equivalence 
point amounts to determining the maximum potential change ob- 
tained upon the addition of small volumes of reagent. This method 
of equivalence point evaluation has proved sufficiently accurate in 
this laboratory to be within slide -rule accuracy. Since the bromide 
and chloride determinations are made on the same solution by means 
of locating two equivalence points on a titration curve having two 
breaks, it will always be necessary to plot a titration curve for this 
analysis. However, in routine analysis where a rough estimate of 
the bromide content is possible, the titration may be carried out 
without plotting up to the beginning of the first break in the curve, 
after which point the plot must be made for most accurate results. 
The carbonate determination also requires a plot since the inflec- 
tion points of the curves must be carefully followed in order to get 
accurate values. However, a scheme similar to the bromide-chloride 
determination may be employed in this determination in order to 
save time and tedium. 

Vigorous stirring of the solution during titration is essential. This 
has been accomplished in this laboratory by employing a small non- 
sparking motor equipped with a glass stirring-rod which operates 
throughout a titration. The actual set-up used in this laboratory is 
pictured in Fig. 2. Many refinements and variations of this set-up 
are possible, but this simple arrangement has proved most satisfac- 
tory. 

Schematic condensations of instructions are always valuable in 
this type of work, and thus a stepwise procedure for each analysis 
will be listed in the glossary at the end of this paper. A complete 
list of the equipment and reagents needed to conduct this analysis 
work will also be included in the glossary as an aid to installation of 
proper laboratory facilities. 



42 



J. G. STOTT 



[J. S. M. P. E. 



Hydroquinone. The method of separating the hydroquinone from 
the rest of the developer solution by extraction from the acidified 
developer with ethyl acetate has been previously worked out. 4 - 5 
The time-consuming and difficult operation has always been the 
determination of the hydroquinone in the organic solvent after 
extraction. This present method makes use of the fact that ethyl 
acetate is somewhat soluble in water. A 2 5 -ml sample of developer is 
placed in a 150-ml extraction funnel and a few drops of 0.04 per cent 
thymol blue solution are added. The solution is then acidified with 
1 : 1 sulfuric acid until the solution turns red, and then 1 ml of acid 




FIG. 2. Typical apparatus set-up. 

is added in excess to assure complete extraction of the hydroquinone. 
Exactly 50 ml of ethyl acetate are added to the extraction funnel and 
the solution is shaken thoroughly for a few moments. The water 
layer is then drawn off into a second 150-ml extraction funnel and the 
operation is repeated using another 50-ml portion of ethyl acetate. 
One extraction removes only 92 per cent of the hydroquinone, and 
thus two extractions are necessary in order to obtain maximum 
accuracy. The water layer is drawn off again and saved for the elon 
determination. The two 50-ml portions of ethyl acetate are then 
mixed together in one of the extraction funnels, and 25 ml of SO 2 wash 



July, 1942] POTENTIOMETRIC METHODS 43 

solution are added (100 gm sodium sulfite, 10 gm boric acid, and 1.0 
gm of potassium hydroxide 1 ). This wash solution removes all the 
sulfur dioxide formed by decomposition of the sulfite in the developer 
upon acidification and extracted by the ethyl acetate. This mixture 
is shaken thoroughly and the water layer is drawn off and discarded. 
Ten mis of the ethyl acetate extract are then pipetted slowly 
into 200 ml of water acidified with 2.0 ml of 1 : 1 sulfuric acid while 
the solution is being vigorously stirred. When all the ethyl acetate 
has gone into solution, platinum and calomel electrodes are immersed 
in the solution, the leads are. connected to the potentiometer, and the 
instrument is balanced. The solution is then titrated with 0.01 N 
eerie sulfate, and the equivalence point is located as previously out- 
lined. With the volumes of developer and ethyl acetate, and the 
concentration of eerie sulfate used in this outline, the following cal- 
culation gives the hydroquinone concentration of the developer : 

(ml of eerie sulfate to equivalence point) X 0.22 = gm of hydroquinine per liter 

In cases where the hydroquinone concentration of the developer is 
unusually low or unusually high, the volumes of developer and ethyl 
acetate used may be varied to give increased accuracy or to save 
titrating time. If the ratio between the developer volume and the 
extract fraction is changed, then the volumetric factor must be 
changed accordingly to give correct results. 

Ceric sulfate is used in this titration because of its high oxidation 
potential giving a large potential change at the equivalence point, 
and because of the fact that eerie ions will not add or substitute on the 
hydroquinone molecule and thus introduce extraneous reactions hav- 
ing a considerable temperature vs. potential coefficient. Precise 
temperature control is not essential in this titration since an absolute 
potential is not required but rather the rate of change of potential on 
addition of unit volumes of reagent. 

Eton. The water layer resulting from the two ethyl acetate 
extractions in the hydroquinone determination is used for the elon 
determination since almost all the hydroquinone has been removed 
by the acid extraction. This hydroquinone-free water layer is again 
placed in a 150-ml extraction funnel and several drops of a 0.04 per 
cent thymol solution are added. The pH of this solution is then 
adjusted by adding 2.0 TV sodium hydroxide until the color of the 
solution turns blue. At this pH the elon will be extracted from the 
solution by ethyl acetate. Exactly 25 ml of ethyl acetate are then 



44 J. G. STOTT [j. s. M. P. E. 

added to the funnel, and the mixture is shaken for a few moments. 
The water layer is then drawn off into a second 150-ml separately 
funnel to be re-extracted, and the above extraction is repeated twice 
more with 15 ml of ethyl acetate and then 10 ml of ethyl acetate. 
The extraction is done three times to extract a maximum of elon from 
the solution since only about 80 per cent is extracted at each opera- 
tion. Three extractions will remove about 99.2 per cent of all the 
elon, and thus the error from this source is minimized. The three 
portions of ethyl acetate are then thoroughly mixed together and 
placed in a 50-ml burette. The tip of the burette is then immersed in 
400 ml of water acidified with 4.0 ml of 1 : 1 sulfuric acid, and 25 ml 
of the ethyl acetate are added slowly to the solution while it is being 
vigorously stirred. When the ethyl acetate has gone into solution 
completely, the titration is run using 0.01 N eerie sulfate in precisely 
the same manner as described for the hydroquinone determination. 
With the volumes and concentrations used in this outline, the elon 
content of the developer may be calculated by the following relation- 
ship: 

(ml of eerie sulfate to equivalence point) X 0.0688 = gm of elon per liter 

Once again the volume ratios may be altered to conform to the 
desired accuracy of the determination. 

Sulfite. The quantitative determination of sulfite in a developer 
is accomplished in a manner previously described. 2 The determina- 
tion is based upon the following reaction : 

Na 2 SO 3 + H 2 O + I 2 -+ 2HI + Na 2 SO 4 

A portion of the developer is placed in a 50-ml burette. Ten milli- 
liters of 1.0 N iodine are placed in a 600-ml Erlenmeyer flask and 
diluted with 100 ml of water which has been acidified with 5.0 ml of 
concentrated hydrochloric acid. This solution is then titrated with 
the developer until the brown color of the solution bleaches out. 
This end point may be determined potentiometrically, but in this 
laboratory experience has indicated that this is entirely unnecessary. 
In fact no starch indicator is needed since the titration is accurate to 
within one drop of developer by observing the color change from the 
characteristic brown color of the iodine to a colorless solution. Using 
the volumes and concentrations herein mentioned, the sulfite content 
of the developer can be calculated from the following relationship : 

630 

. . , : - = gm of Na 2 SO 3 per liter 

ml of developer required 



July, 1942] POTENTIOMETRIC METHODS 45 

Bromide and Chloride. It has been pointed out by Evans, Hanson, 
and Glasoe 1 that "The photographic influence of the presence of 
chloride in the two developers used was investigated over the range of 
concentrations from to 8 gm per liter and it was found to have no 
effect. However, the sensitivity to bromide was such that if the 
bromide analysis included the chloride so that the chloride was replaced 
by an equivalent amount of bromide, an appreciable error would arise." 
Former methods of determining the halide content of a developer 2 
have employed the absorption indicator technic which makes no dis- 
tinction between the bromide and chloride in the developer. It has 
been the experience in this laboratory that if the total halide content 
of the developer is used for precise control work regardless of whether 
only part of that halide has an actual photographic effect, the actual 
function of the halide can not be accurately predicted. In working 
developers it has been found that the ratio between the bromide con- 
tent and the chloride content does not remain the same over ranges of 
total halide concentration, and thus it would seem that a determination 
distinguishing between the two halides is necessary for precise labora- 
tory control. 

A method for determining bromide and chloride in a developer by a 
potentiometric titration had been worked out in this laboratory. 
However, the method proposed by Evans, Hanson, and Glasoe 1 
proved to be more accurate since their treatment of the solution prior 
to titration proved more effective and complete, and thus interfering 
substances were better eliminated. Therefore this basic method is to 
be outlined herein. 

A 100-ml sample of developer is boiled to complete the reduction of 
any silver held in solution by the sulfite and then treated with 40 ml 
of 1 : 1 sulfuric acid to decompose all the sulfite. The acidified solu- 
tion is then boiled to drive off all the dissolved sulfur dioxide and the 
solution is allowed to cool. Eighty cubic centimeters of a solution of 
sodium acetate, 150 gm to a liter of water, are added, and silver and 
calomel electrodes are immersed in the solution and connected to the 
potentiometer. The solution is then titrated with a standard silver 
nitrate solution (14.27 gm per liter), and a plot is made of potential vs. 
volume of silver nitrate added. The first break in the curve will 
come at the bromide equivalence point, and a continuation of tin 
titration will reveal the chloride equivalence point. Since only the 
bromide is of importance, as has been pointed out, the titration may 
be halted at the bromide equivalence point. The concentration of 



46 



J. G. STOTT 



[J. S. M. P. E. 



the silver nitrate is so adjusted that by dividing by 10 the number of 
milliliters of silver nitrate consumed in reaching the bromide equiva- 
lence point, the grams per liter of potassium bromide are immediately 
computed. 



ml of std. AgNO 3 (14.27 gm/liter) 
10 



= gm of KBr per liter 



An illustration of the resulting plot when both the bromide and the 
chloride are titrated is given in Fig. 3. 

Sodium Carbonate. The majority of methods proposed for the 
chemical analysis of sodium carbonate in a developer have made use 
of ,a gas evolution technic. In this type of analysis the developer 



. 






















OF 


BR 

TFRd 


OMID 
dlNA" 


E+CH 
JON ( 


LORIDE 

jsiNe STI 


AG 


10-. 




>< 






















WITH 


SIL\ 


ER 


s. c^ 


LOM 


EL E 


ECT 


RO J DE 


S 


120 






























^ 










MO 


























/ 












L. 






























CHID 


RIDE 


EQU 


VALEi 


NCE 


V) 

J 
































PC 


INT 






5 

3 




| 


































I 

?0 


























/ 














4 

200 


























/ 














no 


| 


















^ 


,x 






























f~- 






































"/ 


--BR 


OMID 


E EO 

POIH 


UIVA 

T 


ENC 
































J 


















































































ML.O 


F STO 


AG 


0(14 


27 G/ 


..) 

















FIG. 3. Typical bromide plus chloride determination. 

solution is treated with some reagent that ties down the sulfite in the 
solution either by converting it to sulf ate or by forming some complex 
salt so that no sulfur dioxide will be formed upon acidification. The 
sample of developer is then acidified in some closed vessel so that the 
evolved carbon dioxide can be collected and measured. Such a 
method of analysis was worked out in this laboratory involving the 
collection of all the gas in a gas burette with a leveling tube attached, 
and the measurement of the total gas volume. This total quantity of 
gas was then transferred to a Hempel absorption pipette filled with a 
solution of potassium hydroxide, and the carbon dioxide was selec- 



July, 1942] POTENTIOMETRIC METHODS 47 

lively absorbed. The resulting gas volume was re-measured and the 
difference between original and final volumes gave the volume of car- 
bon dioxide evolved from the developer upon acidification. A simple 
calculation then gave the sodium carbonate content of the developer. 

This method, because of its basic gas evolution technic, has several 
serious limitations, and experience in this laboratory has indicated 
that this analysis is not always trustworthy. One case arose in this 
laboratory where calcium carbonate peeling off the sides of developer 
tanks coated with hard-water scale caused an error in the final calcu- 
lated result of about 35 per cent of the actual sodium carbonate con- 
centration of the developer. 

It has been found in this laboratory that a titration of carbonate 
developers with standard acid leads to an end point that is inde- 
pendent of calcium carbonate sludge, and can be used as a method for 
determining carbonate. Such a titration is based upon a measure of 
the pH of a solution after each addition of acid, and has an end point 
similar to the previous potentiometric end points. The point at 
which the alkali is all used up or converted to a less alkaline salt gives 
the greatest changes in H with small additions of acid. Such pH 
measurements are usually made with a glass electrode but in the case 
of the usual photographic developers the course of the titration may 
be followed more easily by means of potential measurements made 
with a platinum electrode. Evans and Hanson 6 have shown that a 
stable potential could be measured in an MQ developer, and that this 
potential changed rapidly with pH. The true chemical nature of 
this potential is controversial but for the purpose of a carbonate 
titration this is of no importance, since the end point is determined 
by the point of maximum change of potential and not by any con- 
sideration of the actual value of the potential itself. However, it 
has been found by Cameron 7 that potentials measured in developer 
solutions are affected by the amount of air or oxygen present so that 
vigorous and fairly constant agitation should be used during the 
carbonate titration. 

A 10-ml sample of developer is pipetted into 200 ml of distilled 
water. Either a platinum or a glass electrode is used for this titration 
with the calomel electrode as the standard once again. The solution 
is titrated with 0.10 N hydrochloric acid and a titration curve of 
potential or pH vs. volume of acid added is made. The first break 
in this curve represents the conversion of all the sodium carbonate to 
sodium bicarbonate. The curve form will appear as illustrated in 



48 



J. G. STOTT 



[J. S. M. P. E. 



Fig. 4, and the equivalence point is located as is illustrated by finding 
the exact midpoint of the straight-line portion of the curve. The 
following calculation with the volumes and concentrations used will 
give the actual sodium carbonate concentration of the developer. 

(ml of 0.10 N HC1 to equivalence point) X 1.06 = gm of Na 2 CO 3 per liter 

In cases where other alkalis stronger than carbonate are present in 
the developer, this acid titration type of analysis will give a quantita- 
tive measure of their concentrations. If the above calculation is 
used even if other alkalis, such as sodium hydroxide, are present, the 
total alkali content of the developer will be computed in terms of 



DET5RMirjATIO|N US NG 
N.HCL 



TTG 



ASS VS. CM.OK 



CARfrONA 



FIG. 4. Typical sodium carbonate determination. 

sodium carbonate. This will give a measure of the active alkali in 
the developer computed as if sodium carbonate were the only alkali 
present. This would not necessarily correlate with the photographic 
activity that would result if carbonate were the only alkali present. 

H. In line with the determination of the sodium carbonate in a 
photographic developer is the controversial question of the correlation 
between the ^?H of a developer and its photographic activity. 

It has been impossible in the work conducted in this laboratory to 
associate photographic changes with pH measurements while all 
other constituents of the working developer in question remained 
constant. A working developer in continuous production was studied 



July, 1942] POTENTIOMETRIC METHODS 49 

while the sodium carbonate concentration of the developer was 
progressively decreased. The pH of the developer was periodically 
checked with both a common glass electrode and one of the newer- 
type glass electrodes having no sodium ion correction, and complete 
chemical analyses also were made at the same time. The control 
strips processed at the time of developer sampling indicated that 
little or no correlation between pH and photographic results could 
be found. However, a determination of its carbonate concentration 
gave a close measure of its photographic activity and a direct correla- 
tion between these two variables could be established (Table I). 

TABLE I 

Gamma vs. pH vs. Carbonate Concentration Eastman Fine-Grain Positive Type 

1302 

pH (Glass Electrode with Carbonate Values, 

No Naf Error) Gamma Gm per Liter 

10.38 2.86 68.0 

10.14 2.82 38.7 

10.12 2.77 37.0 

10.11 2.75 35.8 

10.10 2.72 22.4 

10.08 2.70 18.0 

10.10 2.70 18.0 

10.08 2.69 19.1 

10.09 2.70 18.5 

This difficulty has been noticed particularly in the case of positive- 
type developers of the carbonate type having high pH values. The 
impossibility of predicting the alkali concentration from pH measure- 
ments on a positive-type developer is further substantiated by the 
data in Table II. 

Thus it is felt that a careful chemical analysis of the active alkali in 
a positive-type developer using an acid titration technic is essential in 
order to predict the activity of the developer Formerly, the empha- 
sis has been placed upon pH measurements with the chemical analysis 
data functioning as supplementary information. 

However, in the case of negative-type developers having lower pH 
^values, more correlation between the pH of the developer and its 
activity can be established. Moreover, since a chemical determina- 
tion of the borax concentration of a developer is time-consuming and 
of low accuracy, this method of analysis is omitted in favor of a 
measurement of the pU of the developer. Although it is not felt 



50 J. G. STOTT [J. s. M. P. E 

TABLE II 

Table Showing Analysis Data vs. Developer Formula 
Positive Developers 

Analyzed Data, Mixed Formula, Per Cent 

Gm per Liter Gm per Liter Error 

Developer P-l 

Elon 2.80 3.00 -6.7 

Sodium sulfite 78 . 9 80 . -1.4 

Hydroquinone 14.5 15.0 3.3 

Potassium bromide 4.05 4.0 +1.25 

Sodium carbonate (anhydrous) 38.0 40 . 5.0 
H 10.00 

Developer P-2 

Elon 1.40 1.50 -6.7 

Sodium sulfite 39.3 40.0 -1.75 

Hydroquinone 7.22 7.50 3.7 

Potassium bromide 1 . 99 2 . 00 -0.5 

Sodium carbonate (anhydrous) 19.4 20.0 -3.1 
PR 10.06 

Developer P-3 

Elon 0.69 0.75 -8.0 

Sodium sulfite 19.8 20.0 -1.0 

Hydroquinone 3.63 3.75 3.2 

Potassium bromide 1 . 03 1 . 00 +3.0 

Sodium carbonate (anhydrous) 10.30 10.00 +3.0 
H 10.22 

Developer P-4 

Elon 0.25 0.25 0.0 

Sodium sulfite 29.2 30.0 -2.6 

Hydroquinone 4.72 5.00 -5.6 

Potassium bromide 0.78 0.75 +4.0 

Sodium carbonate (anhydrous) 23.1 . 23.0 +0.43 
H 10.30 

that this is the ultimate in proper control of borax-type developers, 
too little practical experience and data have been obtained in this 
laboratory to warrant a more positive commitment. 

DISCUSSION 

It is felt that the aforementioned procedures outline a standardized 
technic for the chemical analysis of photographic developers. The 
analyses are simple and require a minimum of equipment and techni- 
cal skill, and yet incorporate factors that tend to eliminate the so- 



July, 1942] POTENTIOMETRIC METHODS 51 

called "human error." It must be kept in mind, however, that to 
date little data have been published regarding the actual function of 
each constituent of a developer or the magnitude of the photographic 
change introduced by a given change of one or more constituents. 
No universal equation can be formulated for this probem, unfor- 
tunately, since the equation would hold for only one type of film being 
processed in one developing machine functioning under one set of 
conditions. Thus chemical analysis of developers as an instrument of 
processing control is invaluable, but in studying photographic changes 
in terms of developer analysis, the data must be tempered with con- 
siderable experience and knowledge of processing conditions until 
further technology in this field is introduced. 

The author wishes to express his sincere appreciation to D. E. 
Hyndman and H. E. White for their unfailing encouragement and 
many helpful suggestions. Likewise, the many suggestions and 
constructive criticisms of R. M. Evans of the Kodak Research 
Laboratories, and Mr. George Kelch and Dr. Harold Frediani of the 
Fischer Scientific Company have proved invaluable in the completion 
of this work. 

REFERENCES 

1 EVANS, R. M., HANSON, W. T., JR., AND GLASOE, P. K.: "Synthetic Aged 
Developers by Analysis," /. Soc. Mot. Pict. Eng., XXXVIII (Feb., 1942), pp. 
188-206. 

* ATKINSON, R. B., AND SHANER, V. C.: "Chemical Analysis of Photographic 
Developers and Fixing Baths," /. Soc. Mot. Pict. Eng., XXXIV (May, 1940), pp. 
495-496. 

3 KOLTHOFF, I. M., AND SANDELL, E. B. : "Textbook of Quantitative Inorganic 
Analysis," The Macmillan Company, New York, N. Y. (1936), pp. 461-468, 
478-486. 

4 PINNOW, J.: Zeitschrift wiss. Phot. (1912), p. 289. 

'LEHMANN, E., AND TAUSCH, E.: Phot. Korr., 71 (Feb., 1935), p. 71; 71 
(March, 1935), p. 35. 

EVANS, R. M., AND HANSON, W. T., JR.: "Chemical Analysis of MQ De- 
velopers," /. Soc. Mot. Pict. Eng., XXXII (Mar., 1939), pp. 307-320. 

7 CAMERON, A. E. : "The Potentials of Platinum Electrodes in Photographic 
Developers," /. Phys. Chem., 42, (April, 1938), p. 521. 

GLOSSARY 
Schematic Condensation of Analysis Procedures 

Hydroquinone Platinum and calomel electrodes 

(1) Pipette 25 ml of developer into 150-ml extraction funnel. 

(2) Add few drops of 0.04 per cent thymol blue solution. 



52 J. G. STOTT [J. S. M. P. E. 

(5) Add 1 : 1 sulfuric acid until the solution is red, then 1 ml in excess. 

(4) Add 50 ml of ethyl acetate and shake for one minute. 

(5) Remove water layer to second extraction funnel and repeat No. 4. 

(6) Remove water layer and save for elon determination. 

(7) Mix two ethyl acetate portions and add 25 ml of SO 2 wash solution. 

(8) Shake for a few moments and remove and discard water layer. 

(9) Pipette with vigorous stirring 10 ml of ethyl acetate extract into 200 ml 

of water and 2.0 ml of 1 : 1 sulfuric acid in a 1000-ml beaker. 
(10) Titrate to equivalence point with 0.01 N Ce(SO 4 )2 and record volume 

Calculation: 

(ml of 0.01 N Ce(SO 4 ) 2 ) X 0.22 = gm of hydroquinone per liter 
Elon Platinum and calomel electrodes 

(1) Place sample from Hydroquinone No. 6 in 150-ml extraction funnel. 

(2) Add few drops of 0.04 per cent thymol blue solution. 
(5) Add 2.0 N NaOH until solution turns blue. 

(4) Add 25 ml of ethyl acetate and shake for one minute. 

(5) Remove water layer to another 150-ml extraction funnel and repeat No. 4 

using 15 ml of ethyl acetate. 

(6) Remove water layer to extraction funnel and repeat No. 4 using 10 ml of 

ethyl acetate. 

(7) Discard water layer and mix three portions of ethyl acetate extract. 

(8) Place 50 ml of ethyl acetate in burette and add 25 ml with vigorous stir- 

ring to 400 ml of water arid 4.0 ml of 1 : 1 sulfuric acid in a 1000-ml 
beaker while tip of burette is below surface of water. 

(9) Titrate with 0.01 N Ce(SO 4 ) 2 to equivalence point and record volume. 

Calculation: 

(ml of 0.01 N Ce(S0 4 ) 2 ) X 0.0688 = gm of elon per liter 
Sulfite 

(1) Place portion of developer in 50-ml burette. 

(2) Pipette 10.0 ml of 1.0 TV iodine into 600-ml flask with 100 ml of water and 

5.0 ml of cone. HC1. 

(3) Titrate iodine solution with developer until brown color disappears and 

record volume. 

Calculation: 

630 

; = gm of Na 2 SO 3 per liter 

ml of developer to end point 

Bromide and Chloride Silver and calomel electrodes 

(1) Boil 100 ml of developer in 1000-ml beaker for several minutes. 

(2) Add 40 ml of 1 : 1 sulfuric acid and boil for few minutes more. 

(3) Allow to cool and add 80 ml of sodium acetate solution and 100 ml of dis- 

tilled water. 

(4) Titrate with std. AgNO 3 solution (14.27 gm per liter) to equivalence point 

of bromide and to chloride if desired. Record volume. 



July, 1942] POTENTIOMETRIC METHODS 53 

Calculation: 

ml of AgNO 3 to bromide equivalence point 

- = gm of KBr per liter 

Sodium Carbonate Glass or platinum vs. calomel electrodes 

(1) Pipette 10 ml of developer into 200 ml of water in 1000-ml beaker. 

(2) Titrate through carbonate-bicarbonate equivalence point with 0.10 N 

HC1, plotting acid volume vs. potential curve. Determine equivalence 
point from curve. 

Calculation: 

(ml of 0.10 N HC1) X 1.06 = gm of Na 2 CO 3 per liter 

EQUIPMENT 

(This list will include a small overstock in order to accommodate breakage without 
hindering continuation of work.) 
Quantity Type of Equipment 

1 Beckman H Meter, or similar device for potential measurements 

1 5-inch platinum electrode with 30-inch shielded leads 

1 5-inch glass electrode with 30-inch shielded leads (optional) 

1 5-inch silver electrode with 30-inch shielded leads 

1 5-inch calomel electrode with 30-inch shielded leads 

1 Electrode holder 

1 Small non-sparking electric motor complete with stirrer 

1 8-inch hot plate 

1 Wash-bottle, complete 

3 150-ml extraction funnels with ground-glass stop-cock and ground-glass 
stopper 

2 Burette stands with porcelain base 
2 Fisher double burette holders 

1 1000-ml volumetric flask with ground-glass stopper 

2 250-ml volumetric flasks with ground-glass stopper 
2 100-ml volumetric flasks with ground-glass stopper 

4 50-ml burettes 
1 2000-ml beaker 
4 1000-ml beakers 
4 600-ml beakers 
4 250-ml beakers 
4 100-ml beakers 

4 600-ml Erlenmeyer flasks 
1 1000-ml graduated cylinder 

1 250-ml graduated cylinder 

4 100-ml graduated cylinders - 

2 50-ml graduated cylinders 
2 10-ml graduated cylinders 
2 25-ml pipettes 

2 10-ml pipettes 



54 J. G. STOTT 

2 5-ml pipettes 

2 2-ml pipettes 

2 1-ml pipettes 

1 Ring stand 

2 2 I /2-inch iron rings for extraction funnels 

8 500-ml reagent bottles (brown glass with ground-glass stoppers) 

Assorted cork stoppers and rubber stoppers 

Assorted glass stirring rods 

Assorted glass tubing 

Assorted rubber tubing 
4 90-degree ring stand clamps 
4 Pinch-clamps 

CHEMICAL REAGENTS 

(Stock should always contain listed quantities.) 
Raw Chemicals 

Quantity Chemical 

2 lb Boric acid (C. P.) 

5 gal Distilled water 

5 lb Ethyl acetate (C. P.) 

2 lb Hydrochloric acid (concentrated) 

1 lb Potassium hydroxide sticks 

2 lb Sodium acetate 

2 lb Sodium hydroxide 

2 lb Sodium sulfite 

5 lb Sulfuric acid (cone.) 

Standard Reagents and Solutions 

Quantity Solution 

500 ml H = 10.0 buffer solution 
500 ml 0.10 N eerie sulfate (Ce(SO 4 ) 2 ) (stock solution) 
500 ml* 0.01 N eerie sulfate (Ce(SO 4 ) 2 ) (working solution) 
500 ml 1.0 N hydrochloric acid solution (stock solution) 
500 ml 0.10 N hydrochloric acid solution (working solution) 
500 ml 1.0 AT" iodine solution 

500 ml Std. silver nitrate solution (142.70 gm per liter) (stock solution) 
500 ml Std. silver nitrate solution (14.27 gm per liter) (working solution) 
500 ml Sodium acetate solution (150 gm per liter) 
500 ml 2.0 N sodium hydroxide solution 
500 ml 0.04 per cent thymol blue solution 

500 ml Wash solution (SO 2 ) 100 gm sodium sulfite, 10 gm boric acid, 1.0 gm 
potassium hydroxide 

* In mixing 0.01 N Ce(SO 4 )2 solution from the 0.10 N Ce(SO 4 ) 2 stock solution, 
care should be taken to add 5 ml of 1 :1 sulfuric acid to each 100 ml of 0.01 N solu- 
tion to be made. Ceric sulfate is insoluble in pure distilled water, and the acid 
must be added to prevent precipitation of eerie sulfate upon dilution of the 0.10 N 
stock solution. 



CONTINUOUS REPLENISHMENT AND CHEMICAL 

CONTROL OF MOTION PICTURE DEVELOPING 

SOLUTIONS* 

H. L. BAUMBACH** 



Summary. The chemical reactions that take place in a photographic developer 
are discussed in detail. It is pointed out that, following the determination of a 
chemical formula that produces optimal photographic results, the concentration of 
every important ingredient of this solution may be held constant by the use of con- 
tinuous replenishment and chemical control. After a discussion of the theoretical 
considerations involved, details are given for the establishment of picture negative, 
variable-density sound negative, and positive systems in use at the Paramount West 
Coast Laboratory. 

INTRODUCTION 

The ultimate that the user of photographic materials can ask of his 
developing solutions is that they remain absolutely constant, day 
after day and month after month, at exactly the values necessary to 
obtain optimal results. In order that the developer may produce 
consistent results, it is essential that the concentration of each impor- 
tant ingredient remain constant. One method of obtaining this con- 
dition involves the use of a replenishing solution that is added in an 
amount directly proportional to the use of the chemicals within the 
developer and is compounded in such a manner that the concentra- 
tion of every ingredient of the developer remains exactly the same, 
at the constant value desired. 1 This method is called one of con- 
tinuous replenishment, because replenishing solution is added as the 
developer is used, and at any subsequent time the developer is in 
exactly the same condition that it was at the start. The life of the 
solution is thus indefinite, and the amount of film that has been 
processed with it is not significant. 

When a solution of this type is used to develop a photographic 
image, a chemical reaction takes place whereby the developing 
agents, i. e., hydroquinone and metol, sodium sulfite and silver halide, 

* Presented at the 1942 Spring Meeting at Hollywood, Calif.; received April 
14, 1942. 

** Paramount Pictures, Inc., Hollywood, Calif. 

55 



56 H. L. BAUMBACH [J. S. M. P. E. 

react to form hydroquinone and metol monosulfonates, metallic 
silver, and hydrobromic acid. The continued development of photo- 
graphic film in a developer thus causes a decrease in the concentra- 
tions of hydroquinone, metol, and sodium sulfite, and the formation 
of additional hydroquinone and metol monosulfonates and hydro- 
bromic acid. The decrease of concentrations of the developing 
agents and sodium sulfite results in a decrease in the rates of reaction 
of these substances with silver halide and hence extends the time 
necessary to produce a given density or gamma on a photographic 
film. 

All the substances involved in the reduction of the latent image are 
quantitatively exhausted from the developing solution, but it does 
not follow that all the products of the reducing reaction remain in the 
developer. The quantities of products retained depend upon the 
extent of diffusion of the ions from the gelatin layer back into the 
developing solution, the rate of which may be influenced by many 
factors, such as the amount of developer or film agitation, the develop- 
ing time, the condition of the gelatin layer, the temperature, etc. One 
would expect, for example, that a more nearly equivalent quantity of 
bromide ion would be liberated within a negative developer where 
the developing action is quite slow, than would be liberated in a 
positive developer with its high rate of development. 

The products of the development reaction may all influence sub- 
sequent action of the developing solution. The developing-agent 
monosulfonates are themselves developing agents of somewhat less 
reducing power than the parent substances; their developing action 
is of concern only in a developer of high pH value. The bromide ion 
has a pronounced effect upon the developed image; an increase in 
concentration of potassium bromide of 0. 1 gram per liter may reduce 
the density of a developed image by as much as 0.20 but for other 
types of film this same increase will have a negligible effect upon den- 
sity. The hydrogen ion liberated by the developing action slows the 
rate of development by reducing the ionization of the developing 
agents; the extent of this effect is primarily dependent upon the 
buffering salts present, for large amounts of salts of weak acids will 
absorb hydrogen ions to form the weak acid so that there is little 
change in the pH of the solution. 

Every item involved in the reaction of development of a photo- 
graphic image results in the reduction of the activity of the solution 
toward continued development action. A decrease in the concen- 



July, 1942] DEVELOPING SOLUTIONS 57 

tration of hydroquinone, a decrease in the concentration of metol, a 
decrease in the concentration of sodium sulfite, an increase in acidity, 
and an increase in the concentration of bromide ion act to cause a 
lengthening of the developing time required to produce given density 
and gamma values for an emulsion. 

In addition to the action of silver halide upon a developing solution, 
there is the reaction involving the oxygen of the air; while this re- 
action is much the same as 'the previous one, there are important 
differences. The reaction involves hydroquinone, metol, sodium 
sulfite, and oxygen that has dissolved, to form the familiar developing 
agent monosulfonates, practically inert sodium sulfate, and sodium 
hydroxide. Concentrations of hydroquinone, metol, and sodium 
sulfite are reduced, thus causing less developer activity, but the liber- 
ation of sodium hydroxide increases developer activity by raising the 
pH and hence increases the extent of ionization of the developing 
agents. The effect of the increase in pH may more than counteract 
the loss in developing-agent concentration, as is illustrated by the 
action of a developer of the class of D-76, which gains in activity as it 
is subjected to air oxidation. 

It is evident that any developing solution that is being used in a 
developing machine involves factors and reactions that are related in 
a very complex manner. Every reaction involving hydroquinone 
and metol reduces the concentrations of these agents, but does so at a 
rate that depends upon the amount of film developed in a given time, 
the density of the developed image, the extent of developer oxidation, 
the amount of dissolved oxygen, the />H, the concentration of sodium 
sulfite, the temperature, and doubtless other factors. With use, the 
concentration of sodium sulfite also decreases, but the pH may either 
increase, decrease, or remain the same. Sensitometric or visual 
measurements of a particular film give few clews concerning the 
actual condition of the developer after it has been subjected to use. 

It is necessary to use adequate methods of chemical analysis that 
permit a careful study of the behavior of each developer ingredient 
under each condition of use. The type of developing machine used, 
the kind of film being processed, the exposure of the film, the method 
of circulation, the values of gamma and density selected, the rates of 
travel of the film through the machines are factors that compel a 
critical analysis to be made of each situation, in order that an accu- 
rately operating, continuously replenished system may be designed. 

The usual method of developer maintenance is based upon the 



58 H. L. BAUMBACH [J. S. M. P. E. * 

addition of enough additional metol to counteract the density-de- 
pressing effect of increasing amounts of bromide ion, until a condition 
is reached for which the loss of emulsion speed can not be compen- 
sated. Here the useful life of the developer ceases, and it is normally 
discarded and a new batch is prepared. A continuously replenished 
system is based upon the addition of a bromide-free solution to the 
developing solution at a rate sufficient to dilute the bromide liberated 
and hold it at a constant concentration. In addition to diluting the 
bromide as it is formed within the developer, the ingredients that are 
used up in the reaction are to be replaced by the replenishing solution 
at exactly the precise rate necessary to maintain their concentrations 
at a constant value. 

While it is true that continuously replenished systems lead to con- 
siderable economy of operation, the prime reason for their use lies in 
the uniformity of the resulting photographic quality. Under the 
batch system of replenishment, it is not usually possible to cause a 
developing solution to change in the concentrations of all its ingredi- 
ents in precisely the manner that maintains uniform values of density 
and gamma or a uniform picture or sound quality, whereas it is evi- 
dent that the exact maintenance of every developer ingredient at the 
concentration that produces good film quality must result in much 
closer adherence to standards than is possible with the batch system. 

THEORY OF CONTINUOUS REPLENISHMENT 

With an absolutely constant developing solution as a goal, it is first 
necessary to determine the important factors that influence the rate 
of development for a given emulsion. Painstaking research made in 
this laboratory, and doubtless duplicated elsewhere, shows that the 
following factors pertaining to the processing of film require consider- 
ation in order that the processing may be stabilized; factors not in- 
cluded pertain chiefly to film manufacturing and handling variations. 

(1) Strength of the developing solution. 

(2) Degree of developer agitation. 
(5) Temperature of the developer. 

(4) pH of the "short-stop" or fixing solution. 

(5) Temperature during film drying. 

(6) Humidity during film drying. 

Of these variables, only the first presents any real control problem. 
Numbers 2, 3, 5, and 6 are mechanical problems for which engineering 
equipment is available. Number 4 is a chemical problem moderately 



July, 1942] DEVELOPING SOLUTIONS 59 

easy to control. The important chemical variables that influence 
the photographic strength of the developer are : 

(A) Concentration of hydroquinone. 

(B) Concentration of metol. 

(C) Concentration of sodium sulfite. 

(D) Concentration of bromide ion. 
() pH. 

Other factors, such as concentrations of other halides, alkalinities, 
and developing agent monosulfonates, have some effect, and these 
effects are important when used developers are to be synthesized, as 
Evans, Hanson, and Glasoe have shown, 2 but they need not be con- 
sidered in a stabilized system of continuous replenishment, because 
such variables are of second-order magnitude. To explain the man- 
ner in which a continuously replenished system is derived, let us use 
a typical positive developer of the following formula as an illustration : 

Hydroquinone 4 . 00 gm per liter 

Metol 1.00 

Sodium sulfite 40.0 
Potassium bromide 2 . 50 

pH 10.10 

If these concentrations are required in order to produce good film 
quality, the attempt to maintain every ingredient constant requires a 
certain specific procedure. The only item over which the chemist 
has no direct control is the rate of release of bromide ion from the film. 
Since bromide ion can not easily be removed from the developer, it 
can only be diluted. This rate of release is primarily proportional to 
the rate of film travel through the machine and to the integrated 
density of the silver deposit. It is evident that, for the sample case 
above, it will be necessary to add one liter of bromide-free solution to 
the developer for every 2.50 grams of bromide liberated by the film, 
if the concentration is to remain constant at 2.50 grams per liter; 
hence a release of 3.4 ounces of bromide ion, expressed as potassium 
bromide, by 10,000 feet of exposed film in one hour requires dilution 
at the rate of 10 gallons per hour. The total quantity of developing 
solution that is present is of no concern. Whatever quantities of 
other ingredients that are used up in developing this 10,000 feet of 
film must be added to the replenisher in addition to the concentra- 
tions of these substances already present in the developer. 

The rate of release of bromide ion thus becomes the determining 
factor for the rate of replenishment, and when only one certain con- 



60 H. L. BAUMBACH [j. S. M. P. E 

centration of bromide ion is permissible, the replenishment rate be- 
comes fixed at the figure that satisfies the condition of equilibrium. 

Since the rates of exhaustion of the developing agents and the sul- 
fite are in proportion to the rate of release of bromide ion, it is possible 
to replace these substances by using the same solutions that are neces- 
sary to dilute the bromide, even though it is ideally necessary to use 
two different replenishing solutions to maintain a developing solution, 
where each would correct for the specific type of oxidation that the 
developer undergoes. For the halide oxidation, one solution would 
dilute the bromide, correct for the acid liberated, and replace the 
hydroquinone, metol, and sulfite used; for the air oxidation, the other 
solution would correct for the alkali, and replace the hydroquinone, 
metol, and sulfite in different proportion without diluting the bro- 
mide. The latter replenisher would contain the same concentration 
of bromide that was present in the developer. In actual practice, 
the errors introduced by combining these two replenishers are quite 
small, because there is little of one type of oxidation without the 
other. 

Chemical analysis must be used to show the necessary amounts of 
hydroquinone, metol, and sulfite that are to be added to a replenisher 
to replace these items within the developer. The pH of the replen- 
isher must be adjusted to the value that produces the desired pH 
within the developer; this value may be higher, lower, or the same, 
as conditions indicate. 

From the above discussion, the general statement may be made 
that the replenisher must be stronger in hydroquinone, metol, and 
sulfite and weaker in bromide than the developer that is being main- 
tained. The rate of addition of replenisher for a given type of film 
development is determined by the rate of release of bromide and by 
the bromide concentration that is being maintained. 

DERIVATION OF A CONTINUOUSLY REPLENISHED PICTURE NEGATIVE 

DEVELOPER 

Before any continuously replenished system can be considered, it 
is necessary to make a complete chemical study of the reactions that 
take place in the developer as it is used. 3 

Fig. 1 is a record of various chemical analyses for batches of picture 
negative developers, where the concentrations of hydroquinone, 
metol, and bromide are plotted against film footage. This developer 
was being replenished by the addition of a relatively concentrated 



July, 1942] 



DEVELOPING SOLUTIONS 



solution of metol at a rate indicated by sensi tome trie tests. With 
use, the developer increased in bromide concentration because the 
replenishment rate was not sufficient to obtain proper dilution. No 
effort was made to replace hydroquinone since it was necessary to 
utilize the decrease in ratio of hydroquinone to metol to compensate 
for the influence of the increasing bromide upon emulsion speed. 
When the concentration of hydroquinone became low, most of the 
developer activity was carried by the metol, and there was no further 
opportunity to compensate for bromide; at this stage the developer 




10 20 

THOUSAND FEET 



30 



40 



50 



FIG. 1. Analyses of picture negative developer batches for 
various film footages. 

needed to be discarded. Near the end of the useful life of the devel- 
oper, but before the occurrence of any serious emulsion speed loss, the 
concentrations were as follows: 



Hydroquinone 
Metol 

Sodium sulfite 
Potassium bromide 



0.50 gm per liter 
0.80 
50.0 
0.300 



The average of many tests showed that 3000 feet of developed film 
released 1.0 ounce of bromide into this developer. Since the total 
amount of bromide present in the 450 gallons of developer was 18 
ounces and since each strand of the developing machine handles 3000 



62 



H. L. BAUMBACH 



[J. S. M. P. E. 



feet of film per hour, in each hour it is necessary to add 25 gallons of 
bromide-free replenisher for each strand if the bromide concentration 
is to remain constant. Further tests showed that during this hour 
there were used up 4 ounces of hydroquinone, 1.5 ounces of metol, and 
2 pounds of sodium sulfite. Therefore, in the 25 gallons of bromide- 
free solution that must be added per hour, per strand, these amounts 
of chemicals are needed in excess of the concentrations present in the 
developer at equilibrium. While chemical analyses have furnished 
the information necessary to determine replenishment needs, it is 
important that the rate of replenishment be made proportional to the 
rate of film travel through the machine. Charts have been prepared 
that indicate the correct rate of replenishment for any combination of 
development times, and since the system of replenishment is based 
entirely upon film footage, any errors that are the result of unusual 
film exposures are self -correcting and not accumulative. 



j -+- f -.-+ + -- ( -H -h-4 4 -I 



SODIUM SULFITE 












































-METOL AND SULFITE- 
BOOST 



CONTINUOUS REPLENISHMENT- 




10 20 30 

FOOTAGE - THOUSAND FEET 



FIG. 2. Analyses of picture negative developer during establishment 
of continuously replenished system. 



Fig. 2 shows the analyzed concentrations of the picture negative 
developer during the installation of this system. The developer was 
handled as a batch and replenished as such until 40,000 feet of film 
had been processed, after which it was replenished continuously. 
This developer might have been prepared synthetically at the desired 
equilibrium concentrations with identical results. 2 



July, 1942] 



DEVELOPING SOLUTIONS 



63 



A CONTINUOUSLY REPLENISHED SOUND-TRACK NEGATIVE DEVELOPER 

The principles that were outlined for the derivation of a picture 
negative developer apply equally well to the formulation of a similar 
system for sound-track negative. The chief difference lies in the 
character of the negative film ; the sound-track area is much smaller 
than that of the picture ; and the density and gamma values are some- 
what different. Hence for each foot of film developed, the sound- 
track uses considerably less of the developing agents and releases 
considerably less bromide than does the picture. This difference 
would make it possible to replenish the sound-track negative devel- 
oper at a much lower rate, but instead, advantage is taken to operate 
the developer at a lower bromide concentration in order to obtain 
maximum emulsion speed. 



CONTINUOUS REPLENISHMENT 



> 2 


12-18-41 


12-19-41 12-21-41 ( 12-22-41 












> 


o 


e i 


o 
e 





o 




e 










0-02 
04 


e 


> 






e 


8 


o e 









BATCH SYSTEM 


7-2-41 1 7-3-41 1 7-6-41 J 7-7-41 


























> 




, 




_ 






>ENSITV 

5 i 


> 0--. 


J^_0 






k ^ 




S; 





S2 









e 7-~-_ 


| 


*" x . 






X ^ 





^^ 


-04 












^ 

^ft 




X 






II 10 IS 20 2S 30 3ft 4O 45 90 



THOUSAND FEET 



FIG. 3. Calculated densities at constant gamma for sound-track 
negative under continuous replenishment and under the batch system. 

For a development rate of 4000 feet per hour this developer re- 
quires dilution at 35 gallons per hour in order to maintain a potassium 
bromide concentration of 0.160 gram per liter. Because so little 
chemical action takes place in this developer, the replenisher formula 
is very little stronger in developing agents than is the developer. So 
little metol is used that only an additional ounce in 300 gallons is 
necessary in the replenisher. Air oxidation is the dominant oxida- 
tion in this developer ; consequently the pH of the replenisher is made 
considerably less than that of the developer so that the developer pH 
remains constant. 

Continuous replenishment has been of great advantage in this 



64 H. L. BAUMBACH [j. s. M. P. E. 

developer, especially with the use of fine-grain negative films. Tests 
have shown that these films are three times as sensitive to a bromide 
concentration change as the conventional type ; consequently careful 
chemical control is very important. 

Fig. 3 compares, for four consecutive days in each case, calculated 
values of density for a given gamma as plotted against film footage, 
for the two types of developer systems. 

It is evident that continuous replenishment has improved the 
accuracy of development and eliminated differences between be- 
ginnings and ends of runs. 

A CONTINUOUSLY REPLENISHED POSITIVE DEVELOPER 

Because positive emulsions can be made to give good quality when 
the bromide concentration is high in a developer, and because it is not 
important to maintain a high emulsion speed of film used for this pur- 
pose, positive emulsions can be processed with much greater economy 
than can negative emulsions. A continuous system of replenishment 
yields from 100 to 150 feet of developed film for each gallon of re- 
plenisher used in a negative system, whereas there are 1200 feet of 
film processed for each gallon of positive replenisher used. 

As was the case with the negative systems discussed previously, it 
is necessary to select the desired bromide concentration for this 
system, but since almost any reasonable figure can be tolerated, it is 
convenient to use a figure that results from another factor. If no 
squeegee is used to return the volume of developer carried off by the 
film as it leaves the developing unit, an amount of developer is re- 
moved that is primarily a function of the film footage and only secon- 
darily a function of the speed of the film through the machine. There- 
fore, replacement of the volume of developer lost, as film is processed, 
by an equal volume of replenisher will maintain the total volume of 
developing solution at a constant figure and result in an equilibrium 
concentration of bromide. As our particular system is designed, the 
bromide comes to equilibrium at a concentration of 3.50 grams per 
liter. The system of continuous replenishment for the positive 
developer thus is greatly simplified; it operates solely upon the 
basis of maintaining the total volume of developer constant and the 
adjustment of the rate of replenishment to values necessary to satisfy 
this condition. 

The greatest amount of development, of all three systems, occurs 
in the positive system ; and this fact, coupled with the small amount 



July, 1942] DEVELOPING SOLUTIONS 65 

of replenisher used per foot of film developed, causes the positive 
system to have the greatest differential in ingredient concentrations 
between replenisher and developer. For example, in order to main- 
tain the hydroquinone concentration at 2.0 grams per liter in the 
developer, it is necessary to adjust this concentration to about 6.0 
grams per liter in the replenisher. Consequently the positive 
developer requires the most frequent chemical analyses of all the 
systems in order that it may be controlled. 

ERRORS AND CHEMICAL CONTROL METHOD 

In the systems of continuous replenishment that have been dis- 
cussed, the proper replenishment rate has been determined, either 
directly or indirectly, as a function of film footage passing through 
the machine ; the actual exposure that the film has received and the 
amounts of silver actually developed have not been considered. It 
would be expected that differences in integrated developed film den- 
sity would require modification of the replenishing solutions, and 
such is actually the case. However, the large volumes of developer 
solutions that are used contrast with the small degree of chemical 
action that takes place, and over moderately short periods of time 
the developing solution concentrations will show no change. To 
make the system of continuous replenishment practicable for use in a 
production laboratory, it is necessary to adjust the replenishment for 
an average processing condition and then, by periodic chemical 
analysis, to make correction of the developer to its "standard" for- 
mula. If the chemical analyses are frequent enough and correction is 
made immediately, the developer ingredients are held very close to 
constant values. It is impracticable to make corrections in the re- 
plenisher formula to correct for errors in the developer formula unless 
these errors are consistently in one direction. 

Experience has taught us that the number of analyses that are 
needed for efficient control of the developers is not excessive. For 
the picture negative developer, pH determinations are made every 
two hours of use, bromide determinations are made every day, and 
analyses for hydroquinone, metol, and sulfite are performed twice a 
week. The entire system is so close to equilibrium that the greatest 
error that could be attributed to chemical inaccuracies is 0.01 in 
density units. The sound-negative developer is controlled in similar 
fashion, with the one exception that the hydroquinone, metol, and 
sulfite analyses are performed weekly instead of twice every week. 



66 H. L. BAUMBACH 

Here the replenisher is so nearly like the developer, because of the 
small chemical action involved, that the system is extremely stable. 
The positive developer requires analyses for />H and for bromide 
every four hours, and daily analyses for hydroquinone, metol, and 
sodium sulfite. Under these conditions this developer is easily con- 
trolled to 0.02 density unit. 

Chemical analyses are made upon developers for pH by the use of 
the Beckman Laboratory ^vlodel pU. Meter fitted with a Type E 
glass electrode. Determinations of H upon fixing baths are made 
with the Beckman Industrial Model pH Meter, equipped with the 
conventional type glass electrode. Analyses for hydroquinone and 
for metol are made by the extraction of the developing agents with 
ethyl ether and titration with standard iodine solution. 4 Analyses 
for sodium sulfite are obtained by the titration of a known quantity 
of iodine with the developer. 5 Analyses are made for bromide by the 
potentiometric titration of the acidified developer with silver nitrate, 
using a silver electrode and a calomel electrode. 6 

REFERENCES 

1 EVANS, R. M. : "Maintenance of a Developer by Continuous Replenishment," 
J. Soc. Mot. Pict. Eng., XXXI (Sept., 1938), p. 273. 

2 EVANS, R. M., HANSON, W. T., JR., AND GLASOE, P. K.: "Synthetic Aged 
Developers by Analysis," /. Soc. Mot. Pict. Eng., XXXVIII (Feb., 1942), p. 188. 

EVANS, R. M., HANSON, W. T., JR., AND GLASOE, P. K. : "Iodide Analysis in 
an MQ Developer," /. Soc. Mot. Pict. Eng., XXXVIII (Feb., 1942), p. 180. 

3 EVANS, R. M., AND HANSON, W. T., JR.: "Chemical Analysis of an MQ 
Developer," /. Soc. Mot. Pict. Eng., XXXII (Mar., 1939), p. 307 

4 BAUMBACH, H. L. : "The Chemical Analysis of Metol, Hydroquinone, and 
Bromide in a Photographic Developer," /. Soc. Mot. Pict. Eng., XXXIII (Nov., 
1939), p. 517. 

6 ATKINSON, R. B., AND SHANER, V. C. : "Chemical Analysis of Photographic 
Developers and Fixing Baths," J. Soc. Mot. Pict. Eng., XXXIV (May, 1940), 
p. 485. 

6 CROWELL, W. R., AND LUKE, W. W. : "The Potentiometric Determination of 
Halides in Photographic Developers," University of California at Los Angeles. 



THE PRACTICAL ASPECT OF EDGE-NUMBERING 16-MM 

FILM* 



H. A. WITT** 



Summary. The use of the edge-number and how it is generally applied in the 
industry, and the advantages of edge-numbering at 16 frames as a standard for 16-mm 
film are discussed. 

It has been long-accepted practice to edge-number 16-mm film in relatim to 35-mm 
frames. Such practice has proved advantageous in complex films, such as one con- 
structed of some 16-mm film combined with 35-mm to complete a final subject in 
finished form on 16-mm, still maintaining all the advantages gained in the past 
practice by the use of 35-mm. 



It has long been essential in all branches of the industry to edge- 
number 35-mm film. Without the benefit of edge-numbering, many 
hours of additional work would be necessary in handling the multitude 
of details in the assembling of a motion picture production. Edge- 
numbering is found to be of practical value in the laboratory as 
designations of the raw-stock in relation to the sensitometric strips; 
as indications to the laboratory for the printing of rushes or desig- 
nated portions of takes to be printed in some abnormal manner; for 
indicating trick effects ; and for cataloguing and identifying prints in 
vaults. It has proved invaluable in the final assembling of any nega- 
tive where a selection is made in terms of feet of film. 

Although none of these would seem to indicate any necessity for a 
definite standard, the 16-frame interval between edge-numbers has 
become accepted practice and the majority of those involved in such 
detail work have become accustomed to such designations. 

If we are to adopt the newly recommended practice of edge- 
numbering 16-mm film at intervals of 40 frames, we should have a 
new designation bearing no relation to the 35-mm edge-numbering 
with reference to frame count. 

* Presented at the meeting of the Mid-West Section, Feb. 24, 1942; and at the 
1942 Spring Meeting of the Society at Hollywood, Calif. 
** Wilding Picture Productions, Inc., Chicago, 111. 

67 



68 H. A. WITT [j. s. M. P. E. 

As to the relative merits of edge-numbering at 40-frame intervals 
or by any other method, let us take a practical case of a simple pic- 
ture and follow it through its various steps. 

To the cameraman, any scheme of edge-numbering would be ac- 
ceptable, inasmuch as he uses it mainly for the designation of trick 
effects or printer light corrections. The laboratory requires no special 
method of edge-numbering inasmuch as its use is mostly for reference 
and selection. 

The film editor, however, has a very definite use for the edge- 
number. It is used for the designation and selection of material, 
storage, and an indication of synchronism of sound and picture when 
edited as separate track and picture. A film editor could have for 
final assembly into a picture the following combination : 

a 16-mm picture, 

a 35-mm sound-track, to be edited into a picture interspersed with standard 
library stock footage (35-mm). 

The 35-mm track and picture are edge-numbered at intervals of 16 
frames and the 16-mm picture at 40 frames. In synchonizing pic- 
ture action with the voice track, the editor has two different designa- 
tions and as he progresses to the layout of his optical work for normal 
dissolves or fades from his 35-mm stock picture library material to his 
16-mm picture, his procedure becomes highly involved. The possi- 
bility of error is greatly increased because of the usual practice of 
specifying for such trick effects a fine-grain duplicating master posi- 
tive or dupe negative and of ordering such material through the labo- 
ratory according to edge-number. 

If we are to revert to the practice of numbering the working print, 
we should have a problem which is unresolvable under the newly 
recommended practice, because we now have a 35-mm sound-track 
that should bear some designation comparable to that of the 16-mm 
film being run in combination with it. 

In the final assembly of the negative the edge-number is used pri- 
marily as a reference in selecting material, but the actual assembly 
becomes somewhat complex due to the material that is being matched. 
In the final assembling of the 16-mm negative track and 16-mm nega- 
tive picture, the following are to be checked and matched : 

16-mm re-recorded sound-track (negative), 
16-mm original picture (negative), 
16-mm dupe picture (negative), 
35-mm sound-track print, 



July, 1942] EDGE-NUMBERING 16-MM FILM 69 

16-mm picture print, 
35-mm library picture print. 

It is obvious that with these various types of film sizes and edge- 
number designations, a considerable loss of time and great likelihood 
of error on the part of the editor will result. 

In the steps necessary to the final completion of this picture, the 
edge-number designations are frequently of prime importance in 
either selection or layout. We need comparable designations for both 
35-mm and 16-mm film. The suggestion has been made that 16-mm 
film be numbered at intervals of 16 frames, or 32 frames. A 16-frame 
interval would be too small to be of any real value, but by using a 32- 
frame interval and omitting the even numbers and using a star or 
other identifying mark at the 16th frame, the system would become 
comparable to the 35-mm. 



A NEW ELECTROSTATIC AIR-CLEANER AND ITS APPLI- 
CATION TO THE MOTION PICTURE INDUSTRY* 



HENRY GITTERMAN ! 



Summary. A brief description of the principles and early development of elec- 
trostatic precipitation, and a brief description of a new air-cleaner using the electro- 
static principle that generates practically no ozone. Reference is made to recent ap- 
plications of the new precipitator . 



The theory of electrostatic precipitation is not new. In 1824 
Hohlfield described the action of an electrical discharge upon smoke. 
However, no practical significance was attached to his discovery. In 
1884 Sir Oliver Lodge made the first practical use of the principle of 
electrostatic precipitation in the removal of fumes from a lead 
smelter. 

Around 1906 Dr. Cottrell was successful in making use of this 
principle in the removal of fumes in zinc and lead smelters. Dr. 
Cottrell was able to patent his method, turning the patent over to the 
Research Corporation. This corporation has been successful ever 
since in collecting troublesome fumes in any number of industries. 
Nearly all of us are familiar with the Cottrell precipitators which 
this corporation has installed in the smokestacks of many of our 
public utilities. The Cottrell system uses extremely high voltages 
and high currents, which in turn cause the generation of huge amounts 
of ozone, for which reason the system has never been practicable in 
cleaning atmospheric air for breathing purposes, or where the action 
of ozone could be detrimental to product or equipment. 

Principle. It was not until 1931 that Mr. G. W. Penney, manager 
of the Electrophysics Division of the Westinghouse Research Labora- 
tories, was able to announce an air cleaner using the principle of 
electrostatic precipitation that generated practically no ozone. The 
functions of charging and collecting the solid particles in the air were 

* Presented at the 1941 Fall Meeting at New York, N. Y.; received February 
2, 1942. 

** Westinghouse Electric & Manufacturing Co.; New York, N. Y. 
70 



NEW ELECTROSTATIC AIR-CLEANER 



71 



separated and the necessary operating voltages reduced to 13,000 
volts maximum. This was accomplished through the use of a 
collecter cell, consisting of cylindrical rods alternating with fine tung- 
sten wires. Thirteen thousand volts is applied between the wire and 
the rod, creating a strong electrostatic field. As the particles in the 
air-stream pass through this field, all the particles receive a positive 




SOJKCf Of 

POSITIVE HKH 



FIG. 1. Operation of electrostatic air-cleaner. 




Uncleaned 
Air 



Mechanically 
Cleaned Air 



Electrostatically 
Cleaned Air 



FIG. 2. Relative efficiency of air-cleaning methods ( 10,000 cu-f t of 
air through each sample). 

charge. Immediately following this electrostatic field in the line of 
air-flow are placed parallel plates 5 /i mcn apart. These plates are 
charged with 6000 volts d-c. The positively charged particles are 
attracted to the negative plates, grounded and deposited. Fig. 1 
illustrates this principle. 

An outstanding improvement due to this development is the fact 



72 



H. GlTTERMAN 



[J. S. M. P. E. 



that for the first time electrostatically cleaned air can be breathed. 
A power-pack is used to supply the direct current needed for the 
operation of the ionizer section and the collector section. This 
power-pack consists essentially of transformers to increase ordinary 
110-120- volt single-phase, 60-cycle current to the voltages required. 
This current is then rectified by means of rectifier tubes. A pul- 
sating direct current results, which is smoothed out into a pure di- 
rect current by means of capacitors. 

^^^^gmjjjmjmmjjm Extremely small currents are needed. 
- <M|jL~' , For example, 40,000 cubic feet of air 

per minute can be cleaned with an 
|3 expenditure of only 400 watts. 

IfcjlH Efficiency. All our experimental 

work to gain an idea of comparative 
efficiency has been based upon a par- 
ticle-count system of testing. On this 
basis we find that the best of air-filters 
can remove only about 32 per cent of 
the particles in the air-stream. On 
the other hand, electrostatic precipi- 
tation removes as much as 97 per 
cent of the particles. The average 
commercial air-filter removes in the 
neighborhood of 10 per cent of the 
particles. It is safe to say that elec- 
trostatic precipitation is the most 
efficient method of air- cleaning ever 
developed. 

Fig. 2 illustrates the comparative 
efficiency of an ordinary air- filter 
with electrostatic precipitation. This 
method of testing is known as "the 
blackness test." The actual test con- 
sists in drawing air through a standard 

laboratory cloth for a given length of time on the dirty-air side 
of the air-cleaner. The same procedure is followed on the clean- 
air side until a spot of equal discoloration is arrived at. The ratio of 
the time needed to accomplish this is then evaluated and a per- 
centage of efficiency is obtained. As an example, suppose that it 
would take one minute to get a certain blackness on the dirty-air 



il 



FIG. 3. Standard collector cell. 



July, 1942] NEW ELECTROSTATIC AIR-CLEANER 73 

side and ten minutes to get equal blackness on the clean-air side. 
We would then have a ratio in time of 1 :10 or 90 per cent efficiency. 

Fig. 3 shows a standard collector cell. It is 8 inches wide, 36 inches 
high, and 24 inches deep. This cell is capable of handling 600 cubic 
feet of air per minute. The velocity of the air is 300 feet per minute. 

In Fig. 4 we see illustrated the method of placing the cells in an 
ordinary air-distributing duct. It is obvious that this method admits 
of great flexibility in fitting the cells into the duct. The cells have a 
foundation consisting of a bedplate that inclines the cells at an 
8-degree angle from the vertical. Water is used to wash the cells and 
remove the precipitate. The inclination of the cells permits easy 
drainage in the cleaning operation. 




FIG. 4. Method of placing cells in ordinary air-distributing duct 

Self-contained units with one to three cells are available for small 
installations. It is only necessary to attach them to a source of air 
and the proper duct work, combined with a blower system. 

Application. For a number of years after Dr. Penney 's original 
development of this equipment, various trial applications were 
made in the field. Refinements in design were made and finally in 
1938 the apparatus was officially announced as a commercial 
product. 

Since then hundreds of installations have been made. For in- 
stance Precipitron-cleaned air is supplied to huge steel mill motors 
and generators for cooling purposes. It has been found that the old 
methods of air-cleaning allowed many particles to enter the motors 



74 H. GlTTERMAN 

and generators, causing damage to the insulation. In addition, 
periodic shut-downs were necessary in order to blow out the dirt that 
had accumulated. Through the use of Precipitron air-cleaning, 
these troubles have been eliminated. 

In commercial applications offices, restaurants, stores it has 
also been found that Precipitron air-cleaning preserves interior 
decoration by removing the small particles that discolor and dis- 
integrate furnishings. Lighting efficiency can be maintained at a 
maximum since dust does not accumulate on lighting fixtures, walls, 
or ceilings. 

Certain particles in the air-stream are organic in composition, and 
when these particles get into air-conditioning and ventilation ducts 
they putrify and generate obnoxious odors. Electrostatic precipi- 
tation removes these particles from the air-stream and permits more 
pleasant breathing air. As a result the amount of fresh air brought 
into ventilating and air-conditioning systems can be reduced and 
great savings in cooling and heating energy effected. 

The optical and film industries also have been benefited greatly by 
this method of air-cleaning. These industries need the cleanest air 
possible in their manufacturing and processing divisions. All the 
major film-manufacturing concerns use this method of air-cleaning. 
Many of the optical instrument manufacturers have found it indis- 
pensable in their process work. 

Little if any work has been done in electrostatic air-cleaning 
connected with the air-conditioning of modern theaters. It is 
obvious that great economies and improvements can be made through 
the use of this equipment for such applications. We hope to be 
able to announce successful applications in the near future. Ap- 
plications for Precipitron air-cleaning exist in nearly every industry, 
since dust is a universal problem. 



CURRENT LITERATURE OF INTEREST TO THE MOTION PICTURE 

ENGINEER 



The editors present for convenient reference a list of articles dealing with subjects 
cognate to motion picture engineering published in a number of selected journals. 
Photostatic copies may be obtained from the Library of Congress, Washington, D. C., 
or from the New York Public Library, New York, N. Y. Micro copies of articles 
in magazines that are available may be obtained from the Bibliofilm Service, Depart- 
ment of Agriculture, Washington, D. C., at prevailing rates. 



American Cinematographer 

23 (June, 1942), No. 6 

Visual Suggestion Can Enhance "Rationed" Sets (pp. 
246-247) 

Technical Progress of Russia's Film Industry (pp. 248- 
249, 285) 

Animated Cartoon Production Today (pp. 250-251, 282- 
285), Pt. Ill Animation 

Training Films in the U. S. Navy (pp. 252-253, 281-282) 

Choosing Film Materials for Professional 16-Mm Pro- 
duction (pp. 254, 278) 

A.S.C. and Academy to Train Camera Men for Army 
Service (pp. 255, 278) 

Debunking Filtering (pp. 262, 274, 276) 

Making Composition Work for You (pp. 263, 272, 274) 

British Kinematograph Society, Journal 

5 (Jan., 1942), No. 1 
Film Editing (pp. 2-9) 

Future Trends in Laboratory Practice (pp. 10-19) 
Difficulties in Producing Imbibition Prints from a Tri- 
Pack Original (pp. 20-26) 

Educational Screen 

21 (May, 1942), No. 5 
Motion Pictures Not for Theaters (pp. 180-182), Pt. 37 

International Projectionist 

17 (Mar., 1942), No. 3 

Projection Room Uses of Tube Data (pp. 7-9, 20) 
Color of Light on the Projection Screen (pp. 10-12) 



J. W. HOWE 
G. L. IRSKY 

C. FALLBERG 
W. EXXON, JR. 

J. A. LARSEN, JR. 



A. J. STOUT 
P. TANNURA 



S. COLE 

I. D. WRATTEN 

M. V. HOARE 



A. E. KROWS 



L. CHADBOURNB 
M. R. NULL, W. W. 

LOZIER, AND D. B. 

JOY 

75 



76 



CURRENT LITERATURE 



Optical Illusions Producing Three-Dimensional Effects 

(pp. 16-18) T. M. EDISON 

Conserving Critical Materials in the Projection Room 
(pp. 19, 23) 

17 (Apr., 1942), No. 4 
Reducing Trouble-Shooting to Systematized Procedure 

(pp. 7-8, 22) 
New 13.6-Mm Carbons for Increased Screen Light 

9-10) 



L. CHADBOURNE 

M. T. JONES, W. W. 
LOZIER, AND D. B. 
JOY 



Theater Equipment Goes to War (p. 11) 

Review of Projection Fundamentals (pp. 12-14), Pt. I. 

Kinds of Electric Current 
Underwriters Code as It Affects Projection Rooms 

(pp. 16-19) 

Motion Picture Herald 

147 (May 16, 1942), No. 7 
New Screen Aids Television for Theaters (p. 93) 

147 (May 30, 1942), No. 9 
Wartime Conservation in Theater Projection (pp. 23-26, 

31) 

Determining the Efficiency of Your Reflector-Lens Sys- 
tem (pp. 27-28) C. E. SHULTZ 

Optical Society of America, Journal 

32 (May, 1942), No. 5 
Visual Sensitivities to Color Differences in Daylight 

(pp . 247-274) D . L . MACADAM 

The Photographic Reciprocity-Law Failure and the 

Ionic Conductivity of the Silver Halides (pp. 299-303) J. H. WEBB 



SOCIETY ANNOUNCEMENTS 



1942 FALL CONVENTION 



HOTEL PENNSYLVANIA, NEW YORK, N. Y. 
OCT. 27TH-29TH, INCLUSIVE 



After a very successful convention at Hollywood last May, the Society has de- 
cided to continue holding its meetings twice a year, at least so long as the holding 
of conventions does not interfere with the war effort. In fact, it is felt that the 
continuance of technical activities in societies such as our own is important in an 
age such as the present when both peacetime and wartime activities are so highly 
technologic. 

The Fall Convention will be held at the Hotel Pennsylvania, New York, Octo- 
ber 27th to 29th, inclusive. These dates have been chosen in view of the fact that 
the Acoustical Society of America will hold its convention at the same place on 
October 30th and 31st. Those who are interested in the activities of both organi- 
zations may thus take in both conventions in one trip. Details of the Fall Con- 
vention will be published in the next issue of the JOURNAL. Those contemplating 
presenting papers should communicate with the Office of the Society at the 
earliest possible date. (See inside front cover.} 



ADMISSIONS COMMITTEE 



At a recent meeting of the Admissions Committee, the following applicants 
for membership were admitted into the Society in the Associate grade: 

BRIGGS, ALLEN GOEHNER, W. R. 

3117 Calhoun Blvd., 262 Glenwood Ave., 

Minneapolis, Minn. East Orange, N. J. 

CHERRY, HERBERT GOLDBLOOM, LeRoY 

5310 Magnolia St., 3509 Ingleside Ave., 

Philadelphia, Pa. Baltimore, Md. 

FERREL, G. F. HEYER, JOHN 

Box 191, 52 Fordholm Road, 

Belton, Mo. Hawthorn, E. 2, 

FLECK, H. R. Victoria, Australia 

Vaporate Co. Inc., HUGHSON, M. R. 

130 West 46th St., 141 Brantwood Road, 

New York, N. Y. Snyder. N. Y. 

77 



78 SOCIETY ANNOUNCEMENTS 

LAYFIELD, F. E. SCHLOEMER, GENE 

323 South Xanthus, 605 Park St., 

Tulsa, Okla. Rolla, Mo. 

SMITH, D. G. 

PAGES, M. H. Technicolor Motion Picture Corp. 

J T n ' If/' 30 Rockefeller Plaza, 

Bella Vista, B. A. New York, N. Y. 

REISS, MEYER THOMPSON, R. L. 

811 Quincy St., N. W., 1005 East Mulberry St., 

Washington, D. C. Evansville, Ind. 

In addition, the following applicant has been admitted to the Active grade : 

WEISSER, F. E. 
Commack Road, 
Islip, L. I., N. Y. 



JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

VOLUME XXXIX AUGUST, 1942 



CONTENTS 

PAGE 
Cinematography in the Hollywood Studios (1942) 

Black and White Cinematography J. W. BOYLE 83 
Putting Clouds into Exterior Scenes 

C. G. CLARKE 92 
Technicolor Cinematography W. HOCH 96 

Technology in the Art of Producing Motion Pictures 

L. S. BECKER 109 



Stop Calibration of Photographic Objectives 

E. W. SlLVERTOOTH 1 19 



A Review of the Question of 16-Mm Emulsion Position 

W. H. OFFENHAUSER, JR. 123 

The Production of Industrial Motion Pictures 

L. THOMPSON 135 

1942 Fall Meeting, New York, N. Y., October 27th to 
29th 142 



(The Society is not responsible for statements of authors.) 



JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

SYLVAN HARRIS, EDITOR 

Board of Editors 

ARTHUR C. DOWNES, Chairman 

JOHN I. CRABTREB ALFRED N. GOLDSMITH EDWARD W. KELLOGG 

CLYDE R. KEITH ALAN M. GUNDELFINGER CARLETON R. SAWYER 

ARTHUR C. HARDY 

Officers of the Society 

*President: EMERY HUSE, 

6706 Santa Monica Blvd., Hollywood, Calif. 
* Past-President: E. ALLAN WILLIFORD, 

30 E. 42nd St., New York, N. Y. 
^Executive Vice-President: HERBERT GRIFFIN, 

90 Gold St., New York, N. Y. 
** Engineering Vice-P resident: DONALD E. HYNDMAN, 

350 Madison Ave., New York, N. Y. 
*Editorial Vice-President: ARTHUR C. DOWNES, 

Box 6087, Cleveland, Ohio. 
** Financial Vice-P resident: ARTHUR S. DICKINSON, 

28 W. 44th St., New York, N. Y. 
* Convention Vice-President: WILLIAM C. KUNZMANN, 

Box 6087, Cleveland, Ohio. 
* 'Secretary: PAUL J. LARSEN, 

1401 Sheridan St., N. W., Washington, D. C. 
*Treasurer: GEORGE FRIEDL, JR., 

90 Gold St., New York, N. Y. 

Governors 

*MAX C. BATSEL, 501 N. LaSalle St., Indianapolis, Ind. 
**FRANK E. CARLSON, Nela Park, Cleveland, Ohio. 

*JOHN G. FRAYNE, 6601 Romaine St., Hollywood, Calif. 

*ALFRED N. GOLDSMITH, 580 Fifth Ave., New York, N. Y. 
**EDWARD M. HONAN, 6601 Romaine St., Hollywood, Calif. 

*I. JACOBSEN, 177 N. State St., Chicago, 111. 
**JOHN A. MAURER, 117 E. 24th St., New York, N. Y. 

*LOREN L. RYDER, 5451 Marathon St., Hollywood, Calif. 



* Term expires December 31, 1942. 
** Term expires ^December 31, 1943. 



Subscription to non-members, $8.00 per annum; to members, $5.00 per annum, included 
in their annual membership dues; single copies, $1.00. A discount on subscription or single 
copies of 15 per cent is allowed to accredited agencies. Order from the Society of Motion 
Picture Engineers, Inc., 20th and Northampton Sts., Easton, Pa., or Hotel Pennsylvania, New 
York, N. Y. 

Published monthly at Easton, Pa., by the Society of Motion Picture Engineers. 
, Publication Office, 20th & Northampton Sts., Easton, Pa. 

General and Editorial Office, Hotel Pennsylvania, New York, N. Y. 

Entered as second-class matter January 15, 1930, at the Post Office at Easton, 

Pa., under the Act of March 3, 1879. Copyrighted, 1942, by the Society of Motion 

Picture Engineers, Inc. 



CINEMATOGRAPHY IN THE HOLLYWOOD STUDIES (1942) 



Summary. Current practices in cinematography as followed in the Hollywood 
studios are described. Some of the subjects covered are camera equipment, set light- 
ing, operation of camera crews, exteriors and use of booster lights, exteriors taken in- 
doors, make-up, diffusion, coated lenses, use of light-meters, color contrast of sets, set 
and production designs, value of hard light for exteriors and interiors, stand-ins, air 
photography, matching stock shots, Technicolor and bipack, Kodachrome, and mono- 
pack. 



Black and White Cinematography 

JOHN W. BOYLE** 



We have come a long way from the time, some twenty years ago, 
when one was able to recognize the cameraman by the fact that he 
wore his cap backward, just as one could tell the director by his 
puttees. No longer does the producer say, "A rock is a rock; shoot 
it in Griffith Park." Most of the pictures today are made in the 
studios or on the back lot, and it is the job of the director of photog- 
raphy to set the mood of the story by lighting the scenes in the 
proper key and using what photographic effects he can conceive 
and execute on short notice. Although much time is devoted to the 
preparation of the story and dialog of a picture, only on rare occasions 
is sufficient preparation allowed for the technical problems involved 
in set and location planning. Successful pictures result from the 
teamwork of the various technical staffs involved, with the pur- 
pose of achieving the finest artistic and commercial photographic 
results on every picture produced, be it a simple "short" or a 
feature. 

On some of the more pretentious productions "production design- 
ers" have contributed much to further the artistic photographing of 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. 
** Universal Studios, Universal City, Calif. 



JOHN W. BOYLE 



[j. a M. P. E. 



the picture. These production designers are skilled artists, and are 
called in well in advance of the actual production. They become 
familiar with the script, cast, and the amount of money that may 
be spent on the production, and are able to furnish to the director and 
cameraman a series of sketches showing what the actual scenes should 
look like. It is hoped that this kind of preparation will come into 
general use for all types of pictures. 

On this subject, Jack Okey, art director for Alexander Korda's 
Jungle Book, has written the following: 




Scene from Captains of the Clouds showing use of booster lights for 
technicolor exterior shot. (Warner Bros. -First National.) 



"The present-day motion picture is without question the most com- 
plex medium of expression ever devised by man. It is certainly not 
the brain-child of any one person but rather the sum of many indi- 
vidual contributions. All creative talents are called upon to contribute 
their efforts, the maker of pictures among them. Nothing can paint 
a picture of a picture as well as a picture. 

"In reality a motion picture is a series of pictures. The man most 
fitted to create pictures is an artist, with his highly specialized train- 
ing and talent. A man having the power of visualizing an idea and 



Aug., 1942] 



CINEMATOGRAPHY, 1942 



85 



drawing a picture of it that all may see, certainly has a place in the 
making of motion pictures. 

"If the producer would call upon the artist at the same time he 
called upon his writer, and would have him prepare preliminary draw- 
ings or paintings of the subject in mind, there is little doubt that the 
sketches would help both the producer and the writer to decide many 




Effect of water reflections, produced by moving broken 
glass reflecting light from shots. 



matters ; in fact, the director and the chief cameraman should be in- 
cluded in these early conferences. Often a simple sketch will be 
of assistance to the writer in showing plainly what might take thou- 
sands of words to explain. By predetermining questions in this early 
stage, many costly delays and disappointments can be avoided. 
Decisions can be made from the sketches as to the desirable lighting 
effects, wardrobe, characterization, location, sets, and even the very 



86 



JOHN W. BOYLE 



[J. S. M. P. E. 



spirit or mood of the whole production. During the preparation 
period, the artist can make a series of sketches to act as future re- 
minders of the many discussions taking place at the time. As the 
script develops, a series of sketches, known as continuity sketches, can 
be made of the various scenes. They provide advance information, 
and make it possible for the departments to predetermine their work 
in an intelligent and artistic manner. 

"Often on the set, a man under the excitement and stress of the 
many responsibilities resting upon him may not be able to recall read- 




Dolly shot on location, with booster lights, 
rails permit trucking shot of incoming train. 



Dolly tracks alongside 
(Paramount Pictures.) 



ily what he had previously decided to do with a certain situation. A 
quick glance at the sketches will recall the entire scheme to him. The 
sketches can be referred to in the same way in which the written 
script is used. Sketches that break up the written scene into long, 
medium, and close shots can stimulate the creative ability of both 
director and cameraman. They can be guides to strong, beautiful, 
dramatic patterns or compositions. 

"The arrangement of the characters on the screen in good composi- 
tion can do much to heighten the story. As one simple, well known 
example, in a "close-up" of an aggressor the head should be well for- 



Aug., 1942] 



CINEMATOGRAPHY, 1942 



87 



ward on the picture plane, leaving more space behind the head than 
in front of it ; whereas the close-up of the defendant should show more 
space in front of the head than behind it. Sketches can convey such 
things as reminders to all concerned throughout the whole production 
period. 

"The word 'composition' has appeared here several times. It is a 
word almost impossible to define. There are a few elementary rules to 
govern the building of a picture, such as rhythm without repetition, 
the bearing of one thing upon another, the relative influence of lights 




An example of overhead lighting. 

and darks, but these are so self-evident that the painter does not 
think of them while he is at work. He attacks his subject with his 
inherent good taste or talent, composing the drama of the subject 
and injecting into it as much beauty as he can conceive. 

"I do not mean to infer that there have not been many beautiful 
pictures recorded in the past, because there most certainly have. 
What I mean to point out is an easier and surer way, a method of sug- 
gestion and help, a wiser procedure." 

The short time allotted in practice to the cinematographer to read 
the script and prepare for production should be emphasized. It 
is a common occurrence to finish one picture on a Saturday night and 



88 JOHN W. BOYLE fj. s. M. P. B. 

be handed a script for a new picture to start the following Monday 
morning. The cinematographer must then spend Sunday in ac- 
quainting himself with the final version of the script ; arriving on the 
set early Monday morning he finds the painters still painting and the 
set dressers still at work. However, none of these activities have 
deterred the "gaffer" or chief electrician from roughing in the light- 
ing and in placing the overhead units on scaffolds above the 
set. 

With screen stories today overloaded with dialog, it is important 
that the picture be kept moving. This calls for much camera move- 
ment and the shifting of the cast from one position to another through- 
out the set. Such camera movements involve much study in lighting 
and composition, and here again it is only by the complete coordina- 
tion of all departments concerned that the smooth, finished results 
one sees on the screen are possible. The "operative" cameraman 
must know his cue to "pan"; the sound technicians must have their 
cues and must know when and where to move the microphone without 
causing shadows; the mixer must know when to change the fader 
setting; the "grip" must know when and at what speed to "dolly" 
the camera; the assistant cameraman must be constantly alert and 
must anticipate each actor's move and keep the lens focused always 
at the proper distance (most scenes, especially those showing two or 
more actors in the scene, are shot at "split focus," and since the actors 
do not always keep to their marks on the floor, the assistant must use 
his judgment) . Other members of the staff must also know their cues; 
the electricians, for instance, must known when to dim or brighten 
certain lighting units, by the aid of dimmers. A good dimmer opera- 
tor will often compensate for errors of the actors in missing their 
marks by brightening the light if the actors do not come far enough 
forward or by dimming the light if they come too close. It is such 
coordination of all departments that makes for success; sometimes a 
scene that is perfect from the dialog or action standpoint is spoiled 
because someone did not "hit his marks" correctly. Constant at- 
tention and expert handling of the various gadgets by these tech- 
nicians behind the camera have saved many a production hour for the 
company. 

While modern camera equipment has somewhat simplified these 
tasks, it is not possible for every unit, even in the major studios, to be 
equipped with the latest model camera; hence a compromise must 
often be effected under certain conditions. For example, it is com- 



Aug., 1942] CINEMATOGRAPHY, 1942 89 

mon practice to start a scene with a "big head" close-up or insert, 
and then dolly back to a medium or long shot. This calls for variable 
diffusion, and only on the most modern cameras is variable diffusion 
practicable. A compromise adopted in such cases is the use of a 
slight amount of diffusion, which softens the extreme close-up some- 
what and yet is not objectionable in the long shot. With the new 
Fox camera and the latest Mitchell camera, the diffusion is adjustable 
from as soft an effect as may be desired for the big close-up to 
absolute clearness or no diffusion in the medium or long shot. Since 
variable diffusion is usually necessary in making dolly shots, an addi- 
tional assistant is required to manipulate the device, which leads to 
crowding on the dolly or rotambulator. Metro-Goldwyn-Mayer 
Studios have overcome the difficulty by designing a remote-control 
device for operating both the follow focus and the variable diffusion. 

The "set" procedure is as follows : The set is prepared and dressed, 
and the night crew or "swing gang" rigs the overhead lighting units, 
deliberately placing on the scaffolds more units than may be neces- 
sary, as it is more economical to have the units already in place than 
to take time to place them once operations on the set have begun. 
The cameraman and chief electrician having learned whether the 
scene is to be a night or day sequence, the electrical crew proceeds to 
rough in the lighting and wire the necessary fixtures. If the first 
sequence happens to be an interior shot with the sun shining brightly 
outside, preparations are made to light the set in a rather high, or 
day, key. The required, or desired, position of the sun is deter- 
mined, and high-intensity arc lamps are placed so as to project a 
stream of light through a door or window, or both, and cast shadows in 
the proper direction. If both night and day sequences are to be 
photographed on the same set, then a decided contrast in lighting must 
be achieved by keeping the day scenes in a high key and the night 
scenes in a low key. 

The director and cinematographer next confer as to the best way in 
which to play the action called for by the script, and the cast is called 
in and is rehearsed by the director. The cinematographer watches 
the action through a finder which he carries about the set; behind 
him follows an assistant, who marks the floor with small pieces of ad- 
hesive tape indicating points at which the actors stop in their mo- 
tions, while the grip marks the various camera positions so that he 
may lay the track along which the dolly rolls, since a good percentage 
of shots are made from dollies these days. In the meantime other 



90 JOHN W. BOYLE [j. s. M. P. E. 

members of the cast and the crew watch the rehearsal. After the first 
rehearsal the "second team," or "stand-ins/' are brought in, and the 
cameraman and gaffer proceed to light them in their various positions. 
The camera dolly is put into place on its tracks and a mechanical 
rehearsal follows, the stand-ins walking through the action and stop- 
ping at the various positions indicated by the tapes on the floor, for 
the benefit of the electricians, camera crew, and sound men. The 
grips, besides timing their dolly moves and seeing that the dolly oper- 
ates with absolute quiet, search in the meantime for stray light-rays 
that might strike the lens or the diffusion mediums in front of the lens. 
After all lights have been "goboed" and dolly movements corrected, 
the lights are adjusted as may have been found necessary, and the "first 
team" is called in for a dress rehearsal. This final dress rehearsal with 
the actors themselves allows the director and cinematographer to 
make final corrections in lighting and movement. It is not unusual 
during such dress rehearsals to alter or delete certain lines of dialog ; 
such changes in turn necessitate changes in the camera movement and 
dolly timing. After such corrections have been made, microphone 
shadows eliminated from the camera field, and dolly movements 
smoothed out, the crew and cast are ready for a "take." Rarely is the 
first take satisfactory unless the scene is a very simple one. Addi- 
tional takes, or retakes, are made until a satisfactory one is obtained, 
with such lighting corrections being made as might be necessary. 

Because of the variability of the weather, the unwanted noises of the 
outdoors, and other difficulties, more and more exterior scenes are 
being photographed inside the studios. These artificial exteriors are 
more convincing today than they used to be because of many technical 
improvements and advances. The speed of emulsions has been in- 
creased, enabling the cameraman to "stop down" the lens while 
using only slightly additional light. The "special effects" men can 
assist the illusion by hanging leafy tree branches in such positions as 
to cast pleasing shadow patterns on walls and buildings ; slight motion 
of the leaves creates a convincing illusion of outdoors. The use of 
water and glass surfaces, with the proper reflection and agitation, 
leads to many realistic marine effects in both night and day shots. 

Make-up in motion pictures compares to retouching of "still pic- 
tures"; in other words the artists must be "retouched" before they 
are photographed. Naturally there are some whose complexions re- 
quire hardly any make-up, but in most cases make-up is necessary to 
cover slight skin blemishes and smooth out the skin textures. Arthur 



Aug., 1942] CINEMATOGRAPHY, 1942 01 

Miller reports that in the production How Green Was My Valley none 
of the cast wore make-up except the mother and daughter. The 
men were coal miners, and looked the part; however, these same 
actors in a modern story with a drawing room setting would no doubt 
have been made up. Most of the studios are well organized with good 
make-up departments, and their cooperation with the cameramen has 
been most helpful. 

While there is no question that the new high-speed fine-grain pan- 
chromatic emulsions and the improved American-made lenses lead to 
clean-cut photography, the modern electrical equipment is also a very 
important contributing factor. The lighting units have been brought 
well under control; the light can be directed by "barn doors" to the 
spots desired ; and numerous other gadgets may be used for screening 
and softening the light in certain areas. Dimmers and their operators 
play very important parts in almost every scene. Often the camera 
and operators are so close to an actor that their shadows appear in 
the scene; by dimming the lamp causing these shadows the objec- 
tion is eliminated, and the lamp is brought up to its proper bright- 
ness after the camera is out of range. Small units are helpful when 
working in congested areas, and much credit should be given to the 
studio electricians for their ingenuity in handling the small units so 
that they deliver the necessary light without being seen by the 
camera. 

The use of artificial light outdoors is common practice nowadays for 
the simple reason that it has been found to be an economy. Lamps 
on location allow quicker set-ups. The units are more flexible and 
can be placed where desired and, unlike reflectors, need not be placed 
where the sun is shining. While both reflectors and lamps are used 
on location, the lamps are much better for close-ups and intimate 
action ; they can be easily controlled and are not so hard on the artists' 
eyes. For lighting wooded sets and sets in congested areas, lamps are 
indispensible. It is not unusual to finish a day's work on location 
after all the sunlight has gone, in some cases after darkness has set in. 
Matching the artificial light with daylight is an art that most of the 
men have mastered. Likewise, it is sometimes necessary to shoot 
night scenes in the daytime; if the locations are picked with discretion 
and the correct filters and booster lights are used, such night exteriors 
can be handled economically. When production costs rise for one 
reason or another, the studios economize, especially on the lower- 
budget pictures, by using standing sets and cloth backings, and by 



92 CHARLES J. CLARKE [j. S. M. P. E. 

taking other short-cuts. The cameraman is expected to use his art 
and imagination in manipulating the lights and the camera so as to 
cover up such deficiencies. 

Practical cinematography has led to many improvements in the art. 
As newer and better films became available they were rapidly adopted, 
for which reason the art of the cameraman is constantly changing. 
Recommendations and suggestions of the cameramen played a part 
in the development and application of the photoelectric exposure 
meter; in most studios the meter is used to establish the key 
lighting, and, with the increasing use of these precision instruments, 
pictures are now being printed very uniformly, despite the widely 
varying types of lighting and effects employed. 

The method of calibrating lenses by measuring the transmitted 
light with a photoelectric meter, as developed by the Camera Depart- 
ment of Twentieth Century-Fox under Dan Clark, has eliminated 
practially all errors of exposure. A recent test of 150 lenses so cali- 
brated, regardless of focal length, make of lens, etc., and used under 
identical conditions, gave exact exposure at a given stop. It has 
also made possible the effective use of coated lenses, giving greater 
contrast and better definition as compared with uncoated ones. 



Putting Clouds into Exterior Scenes 

CHARLES G. CLARKE* 

A landscape that includes a cloud-flecked sky is far more attractive 
than the same scene without the clouds, particularly in photographic 
landscapes, where, without the benefit of color, the cloudless sky area 
is rendered as an uninteresting expanse of monotone. It has long 
been a major problem of the studios to be assured of obtaining attrac- 
tive exterior scenes, for a great deal of equipment and personnel are 
involved when moving a unit out of the studio. It is not possible to 
decide suddenly to move out to an exterior location; exterior scenes 
must be planned well and at least twenty-four hours in advance. 
During the long California summer, weeks on end follow without 
clouds of any description, and the cameraman is often faced with the 

* Twentieth Century-Fox Film Cprp., Beverly Hills, Calif. 



Aug., 1942] CINEMATOGRAPHY, 1&42 93 

problem of having to photograph scenes with little or no pictorial em- 
bellishment. Heretofore, in the major productions, it has often been 
necessary to "dupe" in clouds after the scenes have been made, and 
sometimes locations at a distance have been chosen where conditions 
indicated that chances of obtaining real clouds were reasonably favor- 
able. The budget for the average production does not permit the 
great expense of either of these alternatives, so a process had to be 
developed by means of which clouds could be produced with depend- 
ability and economy. 

The process to be described uses appropriate photographic trans- 
parencies of real clouds set before the camera, and operates on the 
principle that the barren sky acts as a printing light. The trans- 
parency reduces the light passing to the film in proportion to the den- 
sity gradations of the transparency. On the finished positive the 
whitest "cloud" is of the brightness of the unfiltered sky. As photo- 
graphic emulsions are especially sensitive to blue light, plain sky areas 
are rendered very bright. This characteristic provides a means of 
producing bright, fluffy "clouds." Obviously sky-correcting filters 
are not used, for if the sky is darkened by filters, the brilliancy of the 
"cloud" is destroyed. An appropriate negative of a sky-scape that 
has been exposed with good filter correction is chosen. The view 
should have a perspective and cloud arrangement that will later form 
a pleasing composition when a transparency made from the negative 
is combined with an actual foreground setting. When making the 
positive transparency, the lower portion is "dodged" off so that the 
foreground setting may be photographed through this portion which is 
perfectly clear and transparent. 

The transparency is set up before the lens of the camera and is 
adjusted so that the horizon of the transparency is in proper relation 
to the horizon of the actual scene. A wide-angle lens is employed and 
the smallest lens-stop possible is used so that the transparency and 
the actual scene may be in the same relative focus. In bright sun- 
light, stops from// 14 to //22 are usually desirable. As wide-angle 
lenses at small stops have great depth of field, the focus may be set 
considerably forward of the actual objects in the scene, so that the 
transparency and the most distant parts of the actual scene may be in 
equally sharp focus. Coated lenses are of decided benefit to the sys- 
tem because of the better definition, crisper images, and the lack of the 
"hot spot," often encountered when wide-angle lenses are stopped 
down greatly. 



94 CHARLES G. CLARK [j. S. M. P. E. 

The process is used principally on location where transportation is 
an important factor, for which reason the relatively small size of 1 1 X 
14 inches has been chosen for the transparencies. For stationary 
scenes the transparencies are placed about 18 inches from the lens. 
For panoramic scenes a device is employed that accommodates films 
16 X 40 inches in size. Films are used because they may be curved to 
the radius of the panning camera and thus be at a uniform distance 
from the lens. To overcome displacement or "slippage" the camera 
is so mounted that the nodal point of the lens is at the axis of the 
vertical tilt and panoram. For the stationary set-up the transparency 
is attached to the usual matte-box supports, while for the panoramic 
attachment an auxiliary plate is introduced between the tripod and 
the panoramic head. To this plate is attached the holder for the 
curved plates, for obviously they must remain stationary while the 
camera is panned across the transparency. 

This invention has been in use since late in 1939, and many of the 
productions of this studio have been released with cloud scenes made 
by this process. Among them may be mentioned Brigham Young, 
Hudson's Bay Company, Romance of the Rio Grande, The Cowboy and 
the Lady, most of the Cisco Kid series, and many others. In many 
cases these artificial cloud scenes are edited in with real-cloud scenes, 
and even the cameraman who photographed them both is afterward 
often at a loss to tell which is which. 

Besides the great advantage of being able to create pictorially 
beautiful scenes under unfavorable circumstances, the economic 
importance of the method is very great. In a production such as the 
Romance of the Rio Grande, for example, some forty of the scenes were 
made in this manner. If the clouds had been put in by the matte- 
shot method the cost would have run into many thousands of dollars. 
The complete outfit that was used cost less than $100. The set-up is 
quite simple and is accomplished almost as rapidly as an ordinary set- 
up. The camerman has the visual effect before him on his ground- 
glass. After adjusting the transparency to fit the setting, he is ready 
to make the scene. No further tests or experimentation is neces- 
sary. No alteration of the negative is necessary, and it is processed 
in the usual way. 

In addition to simplicity and economy, the method has the advan- 
tage over the matte-shot method of being able to place action over the 
sky area. In the matte-shot and duping methods, it is necessary to 
keep all action below the horizon, lest such action run over into the 



Aug., 1942] ClNEMATOGfcAPHY, 1942 95 

division line when the sky portions are later exposed in. The cloud 
portions of the transparencies are ordinarily perfectly clear, only the 
areas between clouds having any density. As long as the action stays 
within the "cloud" it may be placed anywhere in the sky. Buildings, 
steeples, moving trees, and the like may extend over the horizon. 
When it is known that close-ups are to follow extreme long-shots in 
the same sequence, a suitable cloud plate is chosen so that the action 
may be properly composed in both. Dark objects or silhouettes may 
extend through the sky portions with no "ghosting" whatever, for 
they are but obstructions to the printing light of the sky. 

As the intensity of the skylight varies greatly, from a direct front- 
light to an extreme back-light, a great number of transparencies of 
different densities would be required to suit all such conditions if some 
means of control were not possible. Such a control is provided by a 
graduated neutral-density filter. For front-lighted and side-lighted 
subjects the light is relatively uniform and control is seldom necessary. 
For back-lighted subjects the sky, hence the printing light, varies 
considerably from sunrise to noon and on to sundown. For such 
shots we carry two densities of the same plate. Adjustments between 
these densities are provided by the graduated neutral-density wedges. 
If the sky is extremely brilliant and the transparency is rendered too 
light in relation to the foreground, the neutral-density filter is ad- 
justed so as to retard the sky area only. When the transparency is 
rendered too dense in relation to the foreground, the filter is inverted 
so as to retard the foreground area, allowing the sky area to "print 
up." Location kits contain about twenty different transparencies 
including examples of front-lighted, side-lighted, and back-lighted 
clouds. In some the composition is arranged so that buildings, trees, 
etc., may extend over the horizon on one or both sides. As the plates 
may be reversed left to right to suit the composition or lighting condi- 
tions, the number of plates required is thereby reduced. From time 
to time new transparencies are made, and before being put into pro- 
duction their densities are tested photographically. Those that meet 
approval are put into the location kits. Needless to say this system 
has the hearty approval of the cameramen. No longer do they dread 
having to photograph exterior scenes on cloudless days. The direc- 
tors likewise, realizing the importance of pictorial beauty in the 
productions, have been most coooperative in arranging action within 
the limits of the method. 

This system is not intended to replace real clouds. It does, how- 



96 WINTON Hocn [J. S. M. P. E. 

ever, offer a fine substitute when nature has not been generous. 
Even when there are real clouds in the sky, the scenes may have to 
be photographed at angles that do not include the clouds. Edited 
together, scenes with and without clouds are inconsistent. This 
method fills in the gaps. Dramatic moods may be created by choos- 
ing suitable cloud formations regardless of the actual sky conditions 
at the time. Hazy skies, which are so difficult to control with color- 
correcting filters, make no difference to the transparency, which re- 
quires only a printing light whether it be hazy or otherwise. By 
using suitably toned or dye-toned transparencies the method may be 
applied to color-photography. 

Rear-projection plates may be made at any time after or before the 
regular production long-shots have been made. Using the same 
transparency for both purposes guarantees that the identical 
cloud effects will prevail in each when the final scenes are edited 
in sequence. It is impossible to discuss here all the adaptations of 
this method. The method is constantly used in this studio, and 
extensions and improvements in the technic of using are occurring 
constantly . 



Technicolor Cinematography 

WINTON HOCH* 

This essay does not in any way pretend to be a comprehensive 
coverage of the equipment, methods, and problems of the Technicolor 
cameraman at the present time, but is intended rather to present some 
of the items that might be of general interest. Inasmuch as the 
general technics of motion picture photography are well known and 
have been frequently discussed in the literature, there will here 
be presented some of those aspects that are peculiar to, or receive 
emphasis from, the fact that the camera is photographing in 
color. 

These aspects arise in very large part before photography, and of all 
the preparation activities that take place before the actual start of 
photography, two that are very important to the Technicolor camera- 
man are color design of the sets and costume color selection. The 

* Technicolor Motion Picture Corp., Hollywood, Calif. 



Aug., 19421 CINEMATOGRAPHY, 1942 97 

importance of proper color design and costume color selection can not 
be overemphasized. The set colors should be chosen with care for 
hue, chroma, and value, and with a knowledge of the costumes to be 
used, the relative importance of the set, its cutting and physical rela- 
tionship to the other sets, and the orientation of these factors with the 
script. While it is true that the cameraman can control the set ef- 
fect to a large extent by his lighting of it, this color control work must 
be carefully handled or the screen result will not be optimum. Obvi- 
ously the more adverse conditions the cameraman meets, the more the 
production is likely to suffer either in screen result or lost production 
time to correct those adverse conditions, or both. These two 
factors of set and costume color probably go farther than any other 
group of factors in representing the difference between a black-and- 
white production and a color production. The net result might be 
termed the "color score" of the picture. It might be compared to a 
musical score sometimes flashing and brilliant and at other times sub- 
dued. It follows that if the problem is ignored, discords usually oc- 
cur. 

Obviously, without sets and costumes in color, the only colors left 
are flesh tones. A very interesting color emphasis effect was demon- 
strated in the RKO picture, Irene, where an entire set was designed in 
neutral tones and the star wore the only color. 

To handle this very important set and costume color contact, the 
Technicolor Motion Picture Corporation has available the services of 
a color control department to advise on the color design of the sets, 
the evaluation of costume colors, and allied problems. This depart- 
ment has a background of experience from all productions, and its 
experience and highly developed judgment are available, through the 
normal functioning of the department, to each new production as it 
comes along. This department is the spearhead of the Technicolor 
photographic activity. 

The make-up problem is handled, as in black-and-white pictures, by 
the studio make-up departments, although the color cameraman does 
have the responsibility of requesting the "touching up" of the make-up 
as it may be necessary, and he very often has special problems that 
require close collaboration with the make-up man. For instance, on 
exteriors with the actors working in sunshine, they usually begin to 
sunburn, and make-up changes must be made in many cases to handle 
these gradually tanning complexions. Frequently this means a new 
make-up problem in order to keep the camera appearance of the flesh 



98 WINTON HOCH [J. S. M. P. E. 

tones the same. It can readily be seen that this can become a difficult 
job. The reverse is also true. As the troupe begins stage work after 
returning from the exteriors, their tanned skins will slowly fade and 
the problem of compensating by make-up continues. Occasionally 
we have had difficulty due to physical exertion on the part of the 
principals, causing faces to flush beneath the make-up, which effects 
the camera appearance. 

The color camera is very discerning of flesh quality, and we find it 
necessary to include in the make-up area the neck and throat, and the 
hands and arms if they show. On rare occasions no make-up at all 
is used, and it is frequently omitted when photographing babies, as 
their clear smooth skin generally needs no correction. 

It should be kept in mind that, generally speaking, the primary 
function of make-up is to correct extremes in colors, cover blemishes, 
and generally reduce the tone range observed in any average group of 
persons. If one will note the varying complexions of people, he will 
readily appreciate that if three or four persons were lined up side by 
side to be photographed, it would be highly desirable and probably 
very necessary to correct the flesh tones and greatly reduce the tone 
spread. This must not be interpreted as meaning that all flesh tones 
should appear alike. Variations of tone are very desirable. It is 
the extremes that are undesirable. Obviously a white man with a 
heavy tan who photographs like an Indian is not a very convincing 
white man. The most critical care is given to the close-ups, especially 
of the principals. The care and attention given to the problem are, 
of course, directly proportional to the screen importance of the skin 
tones. 

A great deal of time and money has been spent in solving the make- 
up problem, and literally thousands of feet of film have been exposed 
and printed on various make-up tests to discover the best make-up 
materials and technics for the color camera. A proper make-up 
requires highly skilled artistry in its application. 

Other important items to the cameraman are his lights. Here, 
color photography again introduces an important factor of which the 
cameraman must be cognizant, and which must be watched very 
closely on certain types of work. That factor is color-temperature. 
Our present three-strip Technicolor cameras are balanced to an aver- 
age daylight color- temperature. For true color rendition, especially 
in the pastel shades and neutral grays, this temperature should 
not vary on the set by more than about =*=250 . 



Aug., 1942] CINEMATOGRAPHY, 1942 99 

There has been in the past some misconception regarding the status 
of incandescent lamps (designated in the studios as "inkies") with 
respect to Technicolor photography. Some people have understood 
that the Technicolor cameras are changed over by filters and prisms to 
accept an unfiltered incandescent-lamp color- temperature. Others 
have indicated that they thought that the camera automatically cor- 
rected any unfiltered inky light that might be added to an arc-lighted 
set. These conceptions are wrong. 

The filters, prisms, and film of our present three-strip Technicolor 
camera are all balanced to daylight and this balance is used both for 
exteriors and interiors. This simplifies the production problem a 
great deal. First of all, there is manufactured and used only one 
set of film emulsions. This means that manufacturing, ordering, 
shipping, storing, exposing, and developing are all standardized for 
one system, with all the obvious attendant advantages, not the least 
of which is a lower negative cost. 

This single standard also simplifies set-lighting problems, both in- 
terior and exterior. All regular Technicolor lighting units have been 
balanced to this daylight color-temperature by actual and repeated 
tests with the Technicolor camera. Therefore, they may all be used 
interchangeably as far as color-temperature is concerned. The only 
other factors governing their use are the very direct functional ones 
such as size of unit, light output of unit, operational characteristics 
of the unit, the type of light that it gives (that is, whether a "hard" 
light or "soft" light), and the unit efficiencies with respect to light 
output vs. current input, and with respect to light output vs. the throw 
required of the unit for the particular job in hand. 

The more common units used for general production are (HI = 
high intensity) : 



The 150-ampere HI arc 

The 120-ampere HI arc 

The white-flame Twin Broad arc 

Inky Sr. spotlight 

Inky Jr. spotlight 

Inky Baby spotlight 



Among others less frequently used but in many cases no less im- 
portant should be mentioned many special converted lamps, a 65- 
ampere HI arc spot, and a 10-kw corrected inky lamp. 



iOO WINTON Hocrt tj. S. M. P. E. 

The light-sources used for photography might be classed in four 
general groups as follows: 

Daylight 

High-intensity arc light 
White-flame arc light 
Incandescent light 

The daylight, of course, is our standard for color- temperature. 
The HI arc lights are all corrected for normal work with a Y-l gelatin 
filter placed in front of the arc light. This filter was especially made 
for Technicolor, using a special non-fading yellow dye supplied by us. 
The exact filter strength is determined by camera test. The white- 
flame arcs were balanced to a daylight color-temperature by the Na- 
tional Carbon Company, and therefore require no filter of any kind. 
The incandescent lighting units must fulfill two requirements to meet 
the daylight color -temperature standard. They must first be 
equipped with incandescent bulbs burning at a color-temperature of 
3380 K, and second, they must be fitted with a tested Macbeth 
glass filter. All General Electric bulbs marked C.P. will burn with a 
color-temperature of 3380 K when operated at their rated voltage. 
It should be emphasized that the rated voltage must be supplied, and 
in the case of the arcs, the proper amperages and proper gap lengths 
and positions must also be maintained. 

Daylight as a source probably presents fewer troubles, although 
very early in the morning and very late in the afternoon trouble is fre- 
quently encountered. An interesting difficulty occurred early one 
afternoon when the smoke from a forest fire filtered the sunshine to 
such a brownish orange hue that it was necessary to abandon the 
location for that day. 

The conditions just outlined do not have to be met at all times, but 
they should be adhered to if a pure white light is necessary and desir- 
able for the work in hand. Certainly there is no limit to the effects 
obtainable with colored lights. For instance, frequently straight un- 
filtered flickering inky lights are used to produce a warm glow on the 
costumes and faces to simulate firelight. Artistic sense and experi- 
ence must dictate the extent to which colored lights are used. The 
colored-light possibilities have been frequently used, perhaps most 
recently and extensively in the colored shadow and live action se- 
quences in Fantasia. Its first featured use in three-color pictures was 
in the first three-color production, La Cucaracha. 



Aug., 1942] CINEMATOGRAPHY, 1942 101 

The rigging and lighting of a color set is similar in many respects to 
that of a black-and-white set, with the exception that lighting units 
balanced for Technicolor are the units used, unless effects are in order. 
Most Technicolor sets rely upon arc-light units for the bulk of the 
lighting. The large sets especially use the larger arc units. Some of 
the very small sets are from time to time lighted entirely by corrected 
inky light. Inky units are valuable also on big sets as auxiliary light- 
ing units. They must be watched for age and cleanliness, as an aged 
bulb and a dirty reflector, filter, and lens can substantially reduce the 
lamp output. Needless to say, cleanliness is also an asset with arc- 
light lenses, and proper maintenance and servicing of all lighting units 
are important. 

Exterior sets and set-ups are also handled in a very similar manner 
to black-and-white set-ups. Scrims, nets, reflectors, and booster 
light all play their part. It should be noted that the so-called gold 
reflector is not acceptable in color work (unless for effect) for obvious 
reasons. 

The color- temperature factor is once more introduced when reflec- 
tors are extensively worked. The term daylight has been advisedly 
used. By definition daylight is the light from the entire sky, includ- 
ing direct sunlight if the sky is clear. Sunshine has a color-tempera- 
ture of about 5,500 K, while blue sky has a color-temperature varying 
from 10,000 to 20,000 K. When reflectors are used as lighting aids 
they select only the sun, which is reflected into the scene, and in- 
troduce a filler light that is warmer in tone than daylight. In ad- 
dition, it must be remembered that the so-called silvered suface, 
which is usually aluminum or tin, reflects slightly less blue than it 
does red and green. This factor also adds slightly to the effect of 
a lower color- temperature. For these reasons reflectors are not 
considered as desirable as booster light for some purposes. This is 
especially true of close-ups where flesh quality is of critical impor- 
tance. 

Process photography in Technicolor is now largely a matter of 
routine. The scenes selected for process work are, of course, subject 
to the usual limitations for that type of work, but astonishing results 
have been obtained. Progress in this field can be largely attributed 
to two factors: improvement in plate quality, and improvements in 
background projector equipment. As Technicolor production film 
is processed day by day the technical crews improve in skill and the 



102 WlNTON HOCH [J. S. M. P. E. 

research groups add their contributions, to the end that the process 
plates now furnished to the studios are specially printed for the opti- 
mum contrast, color-quality, and density required for this type of 
work. The equipment combinations of each studio have been photo- 
graphically tested for color-balance, and this color-balance is also 
taken into account when the plates are printed. 

It has been found that background projectors vary appreciably in 
the color-quality of the projected light. Generally speaking, the 
projectors using reflectors have a little more blue in the light than the 
condenser projectors, although this color-quality varies appreciably 
depending upon the condition of the reflector and the nature of its 
surface, or upon the glass used in the particular condenser set-up in 
use. Some condenser lenses have a very pronounced yellowish cast 
that is not very desirable for color work. 

There has been appreciable .pressure in the last few years aimed at 
increasing the background projector outputs. The present high out- 
puts have resulted from improvements in carbons, objective lenses, 
projector optics behind the objective lens, and lamp house, and in the 
successful combination of several projectors for throwing super 
imposed, matched, and synchronized images onto the process screen. 
Astonishing progress has been made toward increased output, and 
fortunately these developments reached the point where they were 
incorporated into production equipment before the present war ap- 
preciably curtailed progress in this line. 

The Academy of Motion Picture Arts & Sciences and many studios 
and equipment companies have all contributed to this projector im- 
provement problem. As a result, we very frequently photograph 
screens in color more than 20 feet wide, and have photographed, in 
color, process screens approximately 28 feet wide. This size was used 
in the Paramount-de Mille production Reap the Wild Wind. A shot 
has recently been made by the same studio using a split screen includ- 
ing a total camera spread of 50 feet. This was accomplished with the 
aid of two triple relay projectors incorporating the recent improve- 
ments previously mentioned. In this emphasis on large screens it 
should not be forgotten that miniature screens also have their uses, 
and can be successfully handled on the same general basis as the large 
screens. 

The problems faced by the color cameraman in handling process 
photography are generally about the same as those found in all proc- 
ess work. However, he must be very color-conscious and on his 



Aug., 1942] CINEMATOGRAPHY, 1942 103 

guard against an off-color projector light and improperly burning 
foreground lights. He must also be very careful of his foreground- 
to-background balance, as a background that is carried too high will 
often present a burned-out appearance that greatly alters the color 
values of the plate, and destroy the illusion of realism that he is striv- 
ing to create. 

Modern Technicolor camera equipment closely parallels the black- 
and-white studio equipment in its principal operational features and 
functions. There are available, for the camera, lenses of 25, 35, 40, 
50, 70, 100, and 140-mm focal-lengths. They are all in carefully 
calibrated mounts that fit onto a master focusing mount on the cam- 
era. In almost all cases focusing is accomplished by actual measure- 
ment to the focal plane desired, and then the lens is set on this indi- 
cated calibration. Repeated tests have shown that this method is 
more accurate than eye focusing. Eye focusing is seldom resorted to 
unless the focal distance is so short that it exceeds the lens calibra- 
tions. The stop calibrations on the lenses are all photometrically 
determined and calibrated on an arbitrary arithmetic scale. These 
lenses have all been specially corrected for Technicolor work. A very 
interesting and very valuable follow-focus aid, which has been 
standard equipment since the manufacture of the cameras, is avail- 
able to the assistant or technician in the form of a pair of selsyn 
motors. One is attached to the lens mount, and the controlling motor 
is held in the technician's hand, or fastened to some support if desir- 
able, permitting the technician to be 50 feet or more away from the 
camera, and yet maintain accurate control over the lens focus. This 
is of especial value when the camera is put into the sound "blimp," 
making actual rigid mechanical connection with the lens-mount un- 
necessary. This is very helpful on sound shooting inasmuch as the 
camera unit inside the blimp is actually floating in rubber and has no 
direct mechanical contact with the blimp except through this sponge 
rubber. 

The non-rigid relationship between camera and blimp suggests 
another problem that has been solved in a very successful manner. 
That is the problem of attaching a finder for the use of the camera 
operator. Obviously, if it were attached to the outside of the blimp, 
the camera, inasmuch as it is floating, could be framed differently 
from the way indicated by the finder. This was solved by designing a 
very compact finder, and attaching the main optical elements to the 
camera. Auxiliary optical elements are available for use depending 



104 WlNTON HOCH [J. S. M. P. E. 

upon whether the camera is used with or without the blimp. This 
compact design has the additional advantage that this same finder is 
used with the camera for almost 100 per cent of the work; thus only 
one finder and one set of mattes are necessary for each camera, and 
the camera operator has only one set of finder conditions for which to 
make allowances. Auxiliary finder allowances are always necessary 
to compensate for the parallax errors both in front of and behind the 
focal plane for which the camera is adjusted. 

The camera motor arrangement is highly flexible and worthy of 
special note. There are eight types of motors and eight combinations 
of motor-to-camera gears, all of which can be changed in the field. 
The only requirement of the cameraman is to specify the kind of 
shooting expected and the electrical current or the kind of distributor 
system to be used. The regular cameras can also be successfully 
operated running backward at full speed. Speeds higher than 24 pic- 
tures per second, either forward or backward, are not permitted with 
the standard cameras. 

The camera unit has available all the standard camera mounts to 
which the industry is accustomed. The wild camera can be mounted 
on anything from a camera spider to a high tripod, and on any other 
piece of equipment as may be desired, such as dollies, three-wheel 
perambulators, four-wheel velocilators, booms, rotating mounts, etc. 
The camera, incidentally, has been successfully operated in all possible 
positions. 

For sound shooting the standard camera is used in connection with 
either a "barney" or a blimp. The barney is necessarily not so ef- 
ficient from a sound standpoint as the blimp, but it is very useful in a 
great many places. The regular blimp is a highly efficient piece of 
equipment, and of course requires heavier mounts than the wild 
camera, but it can be accommodated on all types of mounts. Those 
most popularly used are the blimp "high-hat," four-wheeled "veloci- 
lator," and a variety of booms. 

There are many items of special equipment available to the Techni- 
color photographer that are far too numerous to mention in detail. 
Among them should be mentioned, however, the variety of equip- 
ment and mounts .used for air photography; the camera blimp and 
mounts used for underwater photography; and the speed-cameras 
capable of consistent operation at so-called six times normal speed, 
or 96 pictures per second. 

The question has been asked if an extra standby camera was kept 



Aug., 1942] CINEMATOGRAPHY, 1942 105 

on the set at all times to replace the camera in use when the film ran 
out, because it took so long to thread the Technicolor cameras. This 
is not true. The actual threading time of a Technicolor camera is 
only about three minutes, for a skilled technician, and many units 
work with only one camera. On major production units, however, 
an extra camera is usually kept on hand, threaded, to prevent any 
possible loss of production time due to many reasons. Some- 
times a reduction of the three-minute threading time is desirable, and 
when sound shooting is involved and a certain emotional tempo or 
mood has been established with the principals, unnecessary mechani- 
cal interruptions are highly undesirable. Frequently the director re- 
quires two cameras on a shot, and the fact that the supply of extra 
cameras is often many miles from the stage has an important bearing 
upon the desirability of this extra camera. The additional cost of the 
extra camera is a very minor item and the camera usually saves much 
more than its cost by the saving of production time. 

This equipment has been in service for many years, and has suc- 
cessfully met the test of almost all climates, altitudes, and conditions. 
The cameras have been in all parts of the world into the crater of 
Mt. Vesuvius, under the sea near Nassau, almost 20,000 feet above 
the Andes in South America, in tropical climates, and in subzero 
temperatures. 

Cartoons and all types of animation photography also should be 
mentioned. The bulk of the cartoon and animation work is now 
handled by adapted black-and-white cameras using the successive- 
exposure method. These cameras are set up with a balanced set of 
three-color filters in the optical system at some point, the filters either 
rotating or sliding, and the color-exposures are made by exposing 
one frame of film through each filter successively. At the head end 
of each roll of film a special chart is photographed, permitting the 
laboratory to identify the various frames. This negative, after de- 
velopment, is printed on a step printer that prints each third frame 
only. Thus the records are separated and the prints handled in a 
manner similar to other standard prints. This method is limited to 
work where no movement takes place during the exposure, and great 
care must be exercised in the lighting, exposure, registration, develop- 
ment, and color-balance of the film. The cameras must be serviced 
to rigid mechanical specifications, and the lenses should be color- 
corrected. A great deal of careful work must be done to set up such 
a system, and reasonable care observed in the shooting. Once the 



106 WlNTON HOCH [J. S. M. P. E. 

system is set up, however, these items are handled largely on a routine 
basis and with reasonable facility This type of photography can 
not be intercut with the standard three-strip negative unless dupe 
negatives are made. 

Other very valuable technics and facilities that are available and 
are very successfully executed in current production today are glass 
shots ; double and multiple exposures ; double and multiple printing ; 
wipes, fades, and lap dissolves made in the laboratory; and many 
combinations of these. The possibilities are numerous. 

While speaking of effects photography, fluorescent materials, 
paints, inks, etc., should be mentioned. This is a field that has not 
received much attention due to lighting equipment limitations ; how- 
ever, it can be accomplished in Technicolor. A very simple test was 
recently made to indicate some of its possibilities. Fabrics colored 
with fluorescent materials were photographed using as an ultraviolet 
source a Type 170 M. R. HI arc, covered by a 12-inch ultraviolet 
Corning filter. The arc unit was positioned 12 feet away from the 
illuminated subject and the spread obtainable with the filter was 
about 6V2 feet at this distance. The brightness of the fluorescent 
fabrics were sufficient to give an acceptable Technicolor negative with 
the camera operating at the normal speed of 24 pictures per second. 

Routine studio Technicolor photography has long since passed the 
experimental stage. It is now handled with the same efficiency and 
dispatch as many black-and-white units. The negative is developed 
at night and the negative reports, negative clippings, and estimated 
printer points are delivered to the Technicolor cameraman on the set 
the following morning. Black-and-white rush prints, if ordered, are 
generally delivered the following afternoon, and the color rush prints 
are delivered the following evening. 

The negative reports and all laboratory contacts are handled for the 
cameraman through the Technicolor camera department, which also 
checks the daily log sheets, and by these log sheets keeps a very com- 
plete record of every production and of every scene photographed on 
that production. The records have proved invaluable, not only to 
the cameraman, but on many occasions to the director and others 
participating in the production. This most excellent coordinating 
agency is extremely valuable. 

Further production flexibility would be available if a single film 
capable of being exposed in any ordinary black-and-white camera 
could be used for a full color record. Technicolor's Research Labora- 



Aug., 1942] CINEMATOGRAPHY, 1942 107 

tory has spent many years in the development of a monopack type of 
film that would fulfill this requirement. Progress on the project was 
reported by Dr. Herbert T. Kalmus, President of Technicolor Motion 
Picture Corporation, to its stockholders in his Annual Report for 
1940, as follows: 

"Your company's research engineers have also been engaged in co- 
operation with Eastman Kodak Company on a process of photography 
employing a single negative or monopack instead of the three strips, 
and on which three emulsions are superimposed on a single support. 
Your company's officers and technicians are frequently asked when 
Technicolor monopack prints will be available. Their current inter- 
est in the monopack process is not primarily for release prints because 
the triple-layer raw film appears inherently to be so expensive that it 
could hardly compete in cost with Technicolor imbibition prints in 
the long run. 

"But your company's officers and engineers do believe that mono- 
pack will be developed to be satisfactory for use as originals from 
which Technicolor imbibition prints can be made. Such an original 
could be exposed through any standard black-and-white motion 
picture camera and should thus have mechanical and cost advantages 
over three-strip negative. 

"Work on this monopack process for originals has been in progress 
for several years, and has lately reached a point of decided encourage- 
ment for certain purposes. At present the monopack research pro- 
gram includes a number of experiments of semi -commercial character 
which are promising for photography where camera size, mobility, 
operating speed, or other special considerations are of extreme im- 
portance. The expectation is that it will first be tried in a limited 
way for the special purposes indicated, to be matched and cut in with 
the larger part of a picture photographed by the three-strip method. 
It should be borne in mind that Technicolor three-strip photography 
is constantly improving in quality so that imbibition prints from 
monopack have not yet overtaken the present quality of imbibition 
prints from three-strip." 

The expectation outlined in Dr. Kalmus' report has been largely 
realized, and since that time monopack has been used in several pic- 
tures, including Dive Bomber and Captains of the Clotids, where shots 
from airplane wing-tips and other difficult locations were required; 
in the industrial field ; in military training films; and in special-effects 
photography where mobility and high speed are important. These 



108 WlNTON HOCH 

uses of monopack are considered as commercial experiments serving 
the dual purpose of fulfilling a special need of increased flexibility in 
the field of color photography and of pointing up production require- 
ments which are not easily determined even on the large-scale test 
basis that characterizes Technicolor's research program. 

Technicolor does not consider that the quality of prints from the 
monopack method of photography has reached the level of quality of 
prints from its three-strip process. This resides in part not in the 
absence of progress with monopack research but in the rapid improve- 
ment of three-strip Technicolor which, like all phases of Technicolor's 
process, receives emphasis from its research group. 

The present monopack process, in latitude, visibility, and tone 
rendition is satisfactory, but the picture texture, in grain and uniform- 
ity, has not attained the smooth, fine texture of three- strip. The 
problems involved in correcting these deficiencies are receiving at- 
tention and progress is being made. 

Technicolor is now and has been for some time definitely on a 
routine production basis, with almost all the technics used in black- 
and-white available in color also. The experimental phases have 
definitely long since left the production field, and have taken their 
place in the Technicolor research department, which is currently very 
active and from which the results flow quietly but efficiently to the 
production field without disturbing changes. 



TECHNOLOGY IN THE ART OF PRODUCING MOTION 

PICTURES* 



LEON S. BECKER** 

The motion picture and the automobile were born at the turn of the century and 
grew up together. Both have their foundations in science and technology, and both 
have profoundly affected our individual and national lives. Their maturity has 
placed them among the five largest A merican industries, yet one is fundamentally an 
an. An automobile is something concrete, tangible, something real; a motion picture 
is light and shadow, laughter and tears, speech and music. The motion picture is an 
art as well as an industry. The motivating forces of the film are drama, comedy, hu- 
man experience yet it could not exist except for the organized efforts of the many 
craftsmen and technicians that make it an industry. Since art and industry are so 
interwoven, a change in technology affects the art of the film, while the demands of the 
art bring about technical improvements. 

This report illustrates the role that technology plays in the conception of the film as 
an art, and the changes that the demands of the art itself have brought about in technic. 
The cameraman's universal focus, the soundman's reverberation chamber, the set de- 
signer's cloth ceiling all have their share in telling a story realistically and dramati- 
cally. Someone's story idea sets this intricate machinery in motion, and from the 
writer, actor, artist, and engineer comes a living entity a combination of arts that 
have been in development since man first learned to record his experiences for posterity. 

When we go to the theater to see a motion picture, we usually go 
because we want to be entertained. We like to feel the presence of 
other human beings around us, because we are gregarious; and we 
want to know about their experiences, because we are curious. If 
the experiences of the characters on the screen are colorful and told 
well, we like the picture and call it entertaining; we recommend it to 
our friends. If the characters are colorless and inconsistent, either 
because of poor acting or poor story, we say that the picture is dull ; 
we do not recommend it to our friends. 

Our reaction to a picture is determined by its realism and its 
dramatic content. The index of realism is dependent upon how 
closely the experiences of the characters in the story coincide with our 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received April 
20, 1942. 

** Warner Bros. Pictures. Inc., Burbank. Calif. 

109 



110 L. S. BECKER [j. s. M. P. E. 

own, or how closely they approach our own ideas of what those ex- 
periences would be in a similar circumstance. A picture about 
colonial days, for example, can not be made using the speech idioms 
or specific behavior of the people of that time, since our ideas of their 
behavior are in terms of today how we would act in the clothes, 
carriages, houses of that century. In other words, for realism, ac- 
curate physical environment in terms of the material things of every- 
day living is necessary, but the psychological processes must be in 
those terms we understand today. 

The index of dramatic content depends upon the story material 
and continuity, the choice of dramatized incidents, camera work, 
editing, sound-effects, music, acting, direction, and numerous other 
elements. A picture about the Civil War may have an extremely 
accurate reproduction of the battle between the Monitor and the 
Merrimac down to the last rivet. But unless that battle has drama 
for the purposes of the story, adequate acting and direction, and 
comparable quality in the other elements, its dramatic content in 
terms of the film as a whole will be practically nil. 

The industry has achieved a notably high standard of realism from 
the standpoint of set design, costuming, research, and the things con- 
cerned with the physical environment of the dramatized story. 
Sound, lighting, make-up, camera, miniature work, process shots, are 
technically adequate and consistently dependable. But it is in the 
application of the technical instruments for the purposes of telling a 
story dramatically and colorfully that the variation in product occurs, 
and that we, as technicians, should attempt to clarify for ourselves 
and for the benefit of the industry. The field is obviously vast in 
scope, and would require the collaboration of many specialists to 
cover the subject adequately. The writer's particular work is in 
sound. Therefore this paper, which attempts to explore the region 
between the purely technical and the artistic, where the technician's 
knowledge of his tools and his individuality and imagination make 
the difference between an outstanding production and just another 
adequate picture, is written from that point of view. 

The story of the motion picture industry as an art is one of con- 
tinual growth and development from the time that Muybridge, in 
1878, took a series of consecutive pictures to study the motion of a 
horse. The purpose was scientific, but the entertainment possibilities 
were quickly recognized. Pioneers built crude cameras of various 
shapes and sizes, experimented with film of varying dimensions and 



Aug., 1942] TECHNOLOGY IN PICTURE PRODUCTION 111 

light-sensitive coatings, and photographed anything in motion. The 
first films had nothing more than side-show value, and pictures of any 
moving objects were sufficient to gain an audience. A moving train, 
a falling building, a bicycle rider, were all adequate subjects for the 
very short films of that day. The possibilities of the film as a story- 
telling medium were not long overlooked, however, and as early as 
1898 a series of shots were spliced together to form a continuous 
story. 

It was not long before the producers of those days recognized that 
this new medium, the moving picture, would revolutionize the art of 
story-telling. The new freedom in space and time opened up unlim- 
ited story possibilities. The film could transport the audience within 
a fraction of a second from the equator to the pole, from the highest 
mountain peak to the most arid desert. The physical restrictions of 
the stage upon action and story locale were shattered. Because of 
the new freedom in space and time, the early film stories were built 
around physical spectacles, such as forest fires, train wrecks, or 
crumbling bridges, that could never have been reproduced satis- 
factorily on the stage. Now, for the first time in human experience, 
the whole world was truly a stage. 

The characters in the first films were "black-and-white" types; 
the hero was handsome, strong, and silent, the heroine pure and 
feminine, the villain mustached and vile. There was no real delinea- 
tion of character, for we must remember that the acting technic was 
directly related to the stage of that time, when the melodrama was 
popular. The physical limitations of the stage, the poor lighting, 
and the distance of the actor from the audience necessitated broad 
gestures and easily recognizable heroes and villains. 

The mobility of the new camera-eye quickly wrought a change in 
acting technic, however. Since the camera and projector could 
magnify the image on the screen to many times its normal size and 
bring the character that much closer to the audience, the broad, 
sweeping gestures of the stage actor had to be subdued in order to be 
credible. This modification in acting technic was so rapid that after 
a decade of development the exaggerated motions of even the greatest 
of the stage stars, when transposed to celluloid, appeared as ridiculous 
to the audiences of the silent days as the early silent pictures appear 
to us now. In 1912, a picture starring the great French actress Sarah 
Bernhardt was released in this country, and was laughed off the 
screen. She had used her stage technic for the film. 



112 L. S. BECKER tf. s. M. P. E. 

In only a few years, therefore, the motion picture had severed many 
of its ties with its parent, the stage. In fact, it was such a lusty, 
self-willed fellow that it succeeded in changing the ways of its parent. 
The appetite of this voracious youngster for greater screen illumi- 
nation improved stage lighting, and the comparative richness of screen 
sets influenced stage scenery and props. Because of the competition, 
stage playwrights had to place greater emphasis upon delineation of 
character through dialog, which the screen was unable to do because 
it had not yet learned to speak. Conversely, the film writer concen- 
trated upon stories of action rather than of character. 

But the complementary element in dramatic story-telling was still 
lacking in the motion picture sound, or rather, synchronized sound. 
The dramatic need for sound was so strongly felt in the silent days 
that directors like D. W. Griffith and von Stroheim suggested sound 
by means of pictures and titles, and even made the actors speak their 
lines for greater realism, though not a syllable came from the screen. 
A title, such as "the sound of the surf told them the sea was near," 
or a picture close-up of a dog howling at the grave of its master, were 
used to give the film more realism and dramatic enhancement. Even 
lapse of time was measured by "pictorial sound" suggestion a milk- 
wagon clattering on the cobblestones to indicate the arrival of morn- 
ing, or a dissolve to the pendulum of a clock to suggest the passage of 
time. And, of course, we remember how music and even sound- 
effects were invariably an accompaniment for the old silents, either 
by a tinny piano, a wheezy organ, or in the case of the first-run movie 
palaces, by a 20-piece orchestra with a specially composed score. It 
was recognized, therefore, long before the synchronized sound-track, 
that since sound and sight together were closer to human experience, a 
motion picture plus music or sound suggestion would be more real- 
istic hence more dramatic. 

The birth of the sound-film stimulated technical progress to an 
amazing degree and resulted in standardizations that proved of great 
benefit to the industry. The speed of the projected film was fixed 
at 90 feet a minute for the reason that the high frequency voice 
sounds, which give to speech intelligibility and to music its timbre 
and brilliance, could not be recorded at a slower rate and still retain 
their definition. For sound-track development purposes film emul- 
sion had to be made more uniform, which not only resulted in more 
consistent sound, but in a better picture as well. The camera, though 
shackled at first by the unwieldy booths and blimps, quickly regained 



Aug., 1942] TECHNOLOGY IN PICTURE PRODUCTION 113 

its mobility and even became more articulate. Set lighting was 
forced to go to the incandescent lamp, because the arc light was too 
noisy for the microphone, and the whole problem of lighting was revo- 
lutionized. Set design, film processing, stage construction, and even 
make-up were benefited by the new addition to the art. 

But as impressive as the technical advances were, the implications 
and possibilities of the enhanced medium as a record and interpreta- 
tion of life were even more imposing. Here, at last, man had found a 
means of transposing his experiences into permanence with the great- 
est realism he had ever known. The art-forms of centuries became 
available. Both the spoken word and literature were now trans- 
latable. Music could heighten the emotional experience to the point 
of pain. And certainly acting again was profoundly affected to the 
extent of a redefinition of the art in terms of the sound-film. Gra- 
dations of character and naturalness were imperative to the realism 
of the synthesis of sound and picture. 

With the birth of synchronized sound, the spoken word, to the 
actor, meant the ability to play a character instead of a type. The 
close-up of sound as well as of camera made underplaying the rule 
and overplaying a caricature. Subtle relations could now exist 
among the characters of a story, and abstract intellectual ideas could 
be expressed. The possibility of portraying characters instead of 
types opened up wider vistas of possible screen material. The vast 
field of human psychology was thrown open to exploration. 

When we hear a sound in real life, such as of someone speaking to 
us, or from a bird in a tree, we can locate the source of the sound be- 
cause we have binaural perception, two separate ears, each of which 
transmits its message to the brain independently of the other. If 
there are two birds in two different trees, we can not only tell them 
apart, but can also distinguish their locations. When we cover up 
one ear, we lose the ability to tell the two sounds apart we put one 
of our direction-finders out of commission ; and we lose also our aural 
ability to distinguish depth or space, except by loudness. With only 
the one ear we have monaural perception. Of course, we still have 
our eyes to provide a sense of depth and space-, but a blind man, 
whose aural sensitivity has been greatly sharpened, can tell tin- space 
and even the size of a room by the lam UM sounds. lletloesit 1>\ the 
amount of reflected sound from the walls and ceiling, as compared t<> 
the amount of direct sound. Singing in the shower is a popular pas- 
time because the ego is bolstered by the reverberation of the room 



114 L. S. BECKER [J. S. M. P. E. 

and the smoothing out of voice imperfections by the roar of the water. 

For the film audience, the source of sound is the loud speaker array 
behind the screen. The original source of sound was the microphone 
on the studio stage. Since there were one microphone and one re- 
cording channel, the sound, for the audience, is monaural. We can 
not distinguish movement or position across the screen. But we can 
create an illusion of movement to or away from the camera, and even 
the feeling of space and environment in the picture, by the use of, 
first, loudness, and second, reverberation. A scene shot in a tunnel, 
or in a mediaeval castle, will be realistic only when the ratio of re- 
flected sound to the original sound is high, and we get the feeling of 
space. 

With the two-dimensional camera, which bears the same psycho- 
logical relation to the eye as monaural sound does to the ear, the 
illusion of depth can be achieved by the proper use of lighting and 
contrast, just as by the manipulation of loudness and reverberation 
with the microphone. And just as the eye can be drawn to particu- 
lar persons or objects by the adjustment of focal-length, so can the 
ear be arrested by the intensification of important sounds and the 
rejection of unimportant ones. If in a scene we wish to draw the 
attention of the audience to a child's toy in the center of the floor, we 
can, by employing an appropriate lens, focus sharply on the toy and 
blur the background. But if we want to draw attention to a music- 
box, and yet keep the other props in focus at the same time, we can 
have the muxic-box play a tune, which will arrest the ear and draw 
the eye. 

The ear, however, is much more imaginative than the eye, and can 
be used for purposes of suggestion to a much greater extent. The 
sound of a coloratura soprano gradually becoming a basso conjures 
up a picture of a phonograph record slowing down, but a visual image 
of the record slowing down does not define the sound it might be a 
symphony or it might be a baby crying. The ear associates more 
imaginatively than the- eye. We hear the sound of crickets and we 
imagine night; but a picture of a night scene does not necessarily 
make our brain hear the sound of crickets. We associate the chirping 
of birds with trees and the country, a siren with an ambulance. The 
eye will not violate action experience, but varying impressions to the 
ear will be credible to the brain. The implications of these psycho- 
logical phenomena for the purposes of the motion picture are tre- 
mendous, and have not been fully realized. 



Aug., 1942] TECHNOLOGY IN PICTURE PRODUCTION 115 

In the decade and a half of the sound-film's existence we have 
learned many things. The writer, actor, and director have developed 
a mode of approach and a background of technic through experience 
as have the technicians. It was learned rather early that if the mo- 
tion picture was to be dramatic and realistic, the technical elements 
that go into its creation should be so utilized that they return into 
oblivion as they do their work. And, axiomatically, if the film is to 
be effective as a medium of expression, the elements that go into its 
creation must merge into the whole. Music, dialog, sound-effects, 
the camera close-up, pan-focus, acting, set design, lighting, cutting, 
and so forth can not be utilized alone, but must be used intelligently 
in conjunction with each other. For the successful synthesis of these 
elements into an organic whole an analysis of these different elements 
in relation to each other must be made. 

The cameraman has a wealth of devices he can use in unfolding 
the story he is telling in conjunction with the other craftsmen. He 
can vary the depth of field or the size of the image. He can choose 
the amount and kind of lighting to be used in a particular scene to 
create a mood or enhance a character. He can undercrank or over- 
crank to change the pace. The camera records a two-dimensional 
picture, yet the cameraman has a three-dimensional point of view. 
He can shoot an object from below or above, from the back or the 
side. Through a knowledge of the habits of the eye and of pictorial 
composition he can draw the attention of the audience to any object 
he may desire for the purpose of the story. It is obvious, then, that 
the cameraman must not only be competent technically, but should 
also be artistically capable. To him with the director, belongs the 
responsibility of making the most of the efforts of the scenic artist, 
prop man, actor, and all the other arts and crafts that go into the 
preparation of the picture for photographing. 

There are, in general, two methods of approach to the problem of 
presenting a specific scene to an audience through the eye of the 
camera; the objective and the subjective. The camera may record 
an incident through the eyes of a fictitious person on the sidelines, or 
through the eyes of one of the characters. For instance, we are 
shooting a scene of a delirious person in a hospital bed. To put over 
the fact that the person is delirious we might show him tossing in his 
bed, or we might show the doctor questioning the nurse about his 
chart: this is the objective approach. Or, we might photograph the 
scene as if through the eyes of the sick man, with the camera going in 



116 L. S. BECKER Lf. S. M. P. E. 

and out of focus on the objects in the room as he is supposed to see 
them in his feverish condition: the subjective approach. The ob- 
jective method is more generally used since it is more direct and 
straightforward. The subjective method is employed more rarely, 
because it usually requires carefully prepared establishing shots to 
be successful. 

The imaginative employment of sound is as unlimited as the 
angles and shadings of the camera. With the wave-filter and equal- 
izer, dialog may be improved, or purposely distorted to simulate 
telephone or radio quality. Music can be thinned to give it a feeling 
of eeriness or distance. The reverberation chamber may give speech 
the quality of an empty hall or the illusion of a voice from another 
world, and music a bigness for dramatic emphasis. Varying the 
speed of the sound-track can make Paul Robeson sound like Minnie 
Mouse, or a chair squeak sound like the creaking of an old pirate ship. 
In the re-recording process, the proper balance between music, dialog, 
and effects can be achieved for maximum enjoyment. Unwanted 
sounds can be deleted and others added. A dramatic sequence can 
be enhanced and the emotional experience greatly heightened. A 
comedy scene can be made more humorous through the imaginative 
use of sound-effects and .music. Just as there are fades and dissolves 
of the picture image, so can there be fades and dissolves of sound for 
time-lapse and continuity. 

Since the human mind can not concentrate on more than one thing 
at a time, it is necessary, for greatest dramatic effect, to point up 
either the visual or the aural element in a scene, but not both simul- 
taneously. In John Ford's classic, The Informer, for instance, the 
tapping of the blind man's cane on the pavement is a beautiful 
example of the subordination. of picture to sound, and the dramatic 
impact it can have. We are interested in the picture of the cane only 
for information as to the source of the sound : the important thing is 
the fear and mounting suspense Gypo feels when he hears the tap of 
the cane, which to him is the forewarning of doom. In Algiers, the 
scene in which the stool pigeon is killed to the musical background of 
the player piano is an illustration of sound in a completely sub- 
ordinate role. The climax of the scene is actually the picture the 
close-up reactions of Pepe, members of his gang, and the informer. 
The piano and dialog create a mood only no dramatic punch stand- 
ing alone. 

Sometimes the impact of the important element can be accen- 



Aug., 1942] TECHNOLOGY IN PICTURE PRODUCTION 117 

tuated and the pace accelerated through the use of a rhythmic 
pattern in the subordinate element. Any device that tends to in- 
crease the concentration of the eye or the ear for the end in view is 
legitimate. For example, we may have a scene in the box car of a 
freight train, showing a man crouched in the corner. The man has 
committed a crime and is escaping. We are interested in showing 
his reactions by the use of a camera close-up of his face. The visual 
element, therefore, is the important one. However, the rhythmic 
clickety-clack of the wheels on the rails plus music is used to heighten 
the visual picture of the man's abject fear of being caught. 

There are times when a rapid shifting of emphasis from sound to 
picture to sound can do much toward relieving monotony and build- 
ing up the pace. A simple example of a plane trying to find the land- 
ing field in a fog, with shifting emphasis from close-ups of the fright- 
ened passengers to the sound of the plane's motors from the ground, 
back to the interior of the plane, and so forth, illustrates the point. 

Dramatically, one of the unfortunate results of the employment of 
sound-effects has been its over-use the cluttering-up of a film with 
sound-effects because they are suggested by the environment. Psy- 
chologically we shut out sounds in real life then why not in the 
film ? Suppose a scene opens with a mother sewing. She is waiting 
for her child to come home from school. Initially, we hear the sound 
of a ticking clock in the corner, the laughter and shouts of children as 
they dawdle on their way, and the chimes of an ice cream man. The 
mother knows that her child is among them. Suddenly we hear the 
screech of brakes and a scream. The mother rushes to the window, 
the camera panning with her. Now, from the moment she hears the 
scream, there is no need for the ticking clock and the noises below. 
Everything suddenly goes dead, except the chimes of the ice cream 
man. 

We achieved two things in this scene with sound: first, the cessa- 
tion of the natural sounds after the scream pointed up the woman's 
reactions with picture; and second, increased the dramatic effective- 
ness by the use of sound contrast in the tinkling chimes. The sus- 
pension of background sounds is acceptable, because subjectively it 
occurs similarly in real life. Sound contrast is an excellent device 
for sharpening the dramatic content of a scene. In Dark Victory, 
when Bette Davis realizes that she is going blind, we hear the sounds 
of children playing an effective use of sound contrast. 

Another type of sound contrast that could be used very dramati- 



118 L. S. BECKER 

cally is silence. By its very nature, sound-film, with its almost con- 
tinuous use of either sound-effects, music, or dialog, could use silence 
as an integral part of the sound technic. Silence could be considered 
as a sound-effect, and treated as such. A picture produced some 
years ago employed silence very effectively. A musician is shown in 
his country cottage composing a symphony. An exterior shot shows 
a landscape of pouring rain and strong wind, with occasional lightning 
flashes. The sounds of rain, thunder, and howling wind are heard. 
The camera moves into the cottage to a close-up of the musician as 
he works on the score. The sound suddenly goes dead, simulta- 
neously with a picture cut to a face close-up. The manner in which 
the musician's deafness was put over had a marked effect upon the 
audience, and illustrated what could be done by treating silence in 
contrast as a sound-effect. 

Sound symbolism has been used effectively in several films either 
as a time-bridge or as a binding agent between scenes. In 39 Steps, 
the landlady finds the body of the dead woman, opens her mouth to 
scream; out of her mouth comes the sound of a train whistle as the 
picture dissolves to a train speeding on its way to Scotland. Here 
sound, in place of the more usual picture, was the binding agent be- 
tween scenes. Sound can be used in association: toward the end of 
Goodbye, Mr. Chips, we see a close-up of the old professor and hear 
the sounds of the boys arriving at the beginning of the school year, 
just as he had heard them many years before. The sounds of the 
boys are used in association, and recall the professor's youth as an 
inexperienced school teacher. Sound can be used in anticipation of 
a dramatic climax: the tapping cane in The Informer, or the child 
murderer in M, who whistles five bars of "In the Hall of the Mountain 
ICing" each time he is about to commit a crime. Sound can be 
suggestive: the train whistle in Vivacious Lady that goes "woo, woo" 
at the end of the picture, or when the sound of bells is heard each time 
Ginger Rogers and Burgess Meredith embrace in Tom, Dick and Harry. 

Much of the really creative work in the use of sound has been in the 
cartoon field. The investigations and experiments that Disney and 
his associates have made with sound-effects and stereophonic sound 
will someday bear fruit and result in much more colorful and dramatic 
live-action production. Such devices as the sonovox, as used in 
Disney's Dumbo, and the vocoder, which makes speech artificially, 
will undoubtedly find their place in telling a motion picture story 
more dramatically. 



STOP CALIBRATION OF PHOTOGRAPHIC OBJECTIVES* 

E. W. SILVERTOOTH** 



Summary. The principle of a null-indicating densitometer has been adapted to 
the measurement of camera lens iris settings. 

An optical system calibrated in accordance with the described technic is rendered 
amenable to precise calculation of the luminous flux per unit area in any part of the 
field, with particular stress laid on the axial condition. 

It is a matter of common knowledge that the practice of photo- 
graphic exposure has had inherent variables, the determination of 
which was subject to large, and often in practice, unpredictable errors. 
Of these undetermined elements such measurements as absolute 
object brightness and the graduations thereof, and effective film 
speed with the plurality of factors affecting that rating, were sig- 
nificant quantities which so eminently enhanced the essential virtue 
of latitude in photographic emulsions. 

With the advent of useful scientific methods of light measurement, 
coupled with the more general adoption of precise control in labo- 
ratory developing procedure, difficulties resulting from correlated 
operations made themselves known and in some circumstances be- 
came predominant in their effects. 

Of these variables, one in particular, the stop calibration of camera 
lenses, has received the attention of Technicolor and of 20th Century- 
Fox, 1 the former in conjunction with their color process, the latter as 
a refinement of their new silent camera. 

Paramount Studio, recognizing the merit of standardized lens 
speed ratings, but at the same time wishing to proceed on a purely 
quantitative basis, set up the following requirements to be met in the 
operation of a calibrating device : 

(1) Results should be reproducible without dependence upon any arbitrary 
standard. 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received April 
14, 1942. 

** Paramount Pictures, Inc., Hollywood, Calif. 

119 



120 



E. W. SlLVERTOOTH 



[J. S. M. P. E. 



(2) The method should be amenable to exact calculation of effective actinic 
energy per unit of area in the focal plane. 

(5) It should be reproductive of axial densities. 

(4) Independent of brightness of light-source. 

(5) Independent of amplifier, photocell, and meter linearity, as well as of ampli- 
fier gain. 

(6) It must be foolproof, accurate, and rapid in operation. 

With the above-listed desired properties in mind, a device was con- 
structed for use by our Camera Department. Referring to Fig. 1, 
light from source A is collimated by the low focal ratio objective B, 
forming a parallel beam of uniform cross-section. Either the lens 
under test or the standard aperture may be placed at C. The stand- 




FIG. 1. Device for stop calibration of photographic objectives. 

ard aperture consists of a metal plate with a circular perforation of 
area equal to the theoretical aperture of the lens, diminished by a 
factor determined from the transmission characteristic of the given 
objective. Since studio production camera lenses (treated, in our 
case) do not vary widely in this respect, this factor has been assigned 
a value of 90 per cent. Untreated lenses, or more highly absorbing 
optical systems in wide variety could similarly be calibrated, but with 
an auxiliary notation of percentage transmission incorporated in the 
engraving operation. 

The lens at C is followed by the factor-of-two step-wedge D, thence 
by the diffusion disk E and the photocell F. Somewhere in the 
vicinity of objective B is included an auxiliary photocell J, illumi- 
nated from source A through the adjustable iris H and diffusion disk 



Aug., 1942] 



STOP CALIBRATION OF OBJECTIVES 



121 



/. Photocells F and / are meshed to the input of a two-stage direct- 
current amplifier 2 K the output of which is fed to a zero-center-scale 
microammeter, or null indicator L. The sensitivity of the instru- 
ment is adequately controlled by means of a meter shunt. 
The method of operation is as follows : 

(1) The standard stop (one for each focal length lens) is placed at C. 

(2) By means of H, a light balance is secured between photocells F and /. 

(5) The standard stop is replaced by the lens under test ; the lens iris is adjusted 
until balance is again attained. 

(4) Wedge D is shifted one stop, and the lens iris setting is altered to compen- 
sate. This step is repeated until the lens is completely calibrated. 




FIG. 2. Photograph of the device. 



Because of the limited window area at E, it is necessary in the 
described unit to match standard stops with iris openings of //ll or 
//16. A more elegant method would be that of replacing the diffusion 
disk E with an integrating sphere of adequate size. 

It is evident from the foregoing description that camera lenses so 
calibrated will yield duplicate densities in the center of the focal sur- 
face under similar conditions of exposure. The importance of this 



122 E. W. SlLVERTOOTH 

feature is best appreciated when consideration is given to the wide 
variation from lens to lens of off- axis illumination curves. 3 The very 
individuality of this circumstance in a lens system dictates the ne- 
cessity for axial calibration if the useful prediction of focal-plane 
illumination is to be available for the more significant calculation of 
optimum light level requirements on sets. This conclusion is predi- 
cated on the assumed condition that the center of the scene is gener- 
ally of greatest importance. An interesting ramification of the device 
in this connection lies in the possibility of rotating the lens under test 
about the rear nodal point, thus conveniently securing information 
related to the off-axis flux values. 

In conclusion, it is believed that a precision method of lens-stop 
calibration has been adequately defined for all practical photographic 
applications; and further, that the elimination of an arbitrary stand- 
ard for comparison purposes has provided a generally available cali- 
brating technic. 

REFERENCES 

1 CLARK, D. B., AND LAUBE, G. : "Twentieth Century Camera and Acces- 
sories," /. Soc. Mot. Pict. Eng., XXXVI (Jan., 1941), p. 50. 

* LYONS, W., AND HELLER, R. E.: "A Direct Reading Vacuum-Tube Milli- 
voltmeter," Electronics (Nov., 1939), p. 25. 

3 BENFORD, F.: "Illumination in the Focal Plane," J. Opt. Soc. Amer. (May, 
1941), p. 362. 



A REVIEW OF THE QUESTION OF 16-MM EMULSION 

POSITION* 



WM. H. OFFENHAUSER, JR.** 



Summary. There are several standards anomalies in 16-mm little realized no 
only by many engineers but also by many of those who daily use the medium. 

While there is but one 35-mm emulsion position the standard position, the emul- 
sion facing the light-source there are two emulsion position in 16-mm the "stand- 
ard" position, in which the emulsion faces the screen; and the "non-standard" posi- 
tion, in which the emulsion faces the light-source. What the non-standard position 
films may lack in millions of feet used per month, is made up in great measure by 
their 5 to 1 processing-cost ratio and their higher first cost. 

Commercial projection equipment generally has ignored these more costly films 
and chosen to compete in the low-cost low-quality black-and-white print market. 
Not one projector manufacturer supplies as standard equipment today a directional 
loud speaker of suitable efficiency and transient characteristics for high-quality re- 
production; only one manufacturer supplies as standard equipment a sound pro- 
jector whose sound optics are one-half mil in width and may be refocused properly to 
project "non-standard" emulsion position prints. 

While 16-mm black-and-white print quality is generally bad and the resultant pro- 
jected picture and sound likewise bad when compared with 35-mm theatrical projec- 
tion, this condition can be corrected almost overnight if Government specifications for 
16-mm prints and for 16^mm sound projectors and loud speakers will call for modern 
16-mm materials, modern specialized 16-mm methods, and modern equipment. 
Unit cost increases for the improved quality are inevitable; the increase in effective- 
ness, however, will far more than compensate for the relatively small increases in 
unit costs that result. One commercially available system for achieving the desired 
standard of quality is described. 

It has become quite common in the last few years for a projectionist 
of 16-mm film to ask himself the question: "Which side is up on this 
film?" and in many cases the quality of the projected show, in par- 
ticular the sound quality, hinged on whether the all-important answer 
was right or wrong. When a 16-mm sound-film is properly threaded 
in a projector, the emulsion of the film may face the screen, which 



* Prepared at the request of the Standards Committee; presented at the 1942 
Spring Meeting at Hollywood, Calif. 

** Precision Film Laboratories, New York, N. Y. 

123 



124 W. H. OFFENHAUSER, JR. [J. S. M. P. E. 

position is called the "standard emulsion position," or it may face 
the projector light-source, the "non-standard" emulsion position. 
Sixteen-mm sound-films for projection today may be expected to be 
found in both kinds. 

When the original emulsion position question was first brought up 
for consideration, it was the feeling of ah 1 concerned that reversal 
originals would be of key importance, and accordingly, the present 
standard 16-mm emulsion position was agreed upon. Since in a cam- 
era the emulsion of the film faces the lens, the standard emulsion posi- 
tion in a 16-mm projector therefore would be the position in which 
the emulsion also faces the lens of the projector. (The film used is 
the original film the original reversal.) 

Optical reduction printing from 35-mm was then made to conform 
to this standard, and since the decision was made, all reduction print- 
ing equipment for copying 35-mm to 16-mm has been adjusted to pro- 
duce only standard emulsion position prints. In the meantime, 
original reversal film with sound as a potential source never really 
developed, and in the earlier stages of 16-mm sound-film, practically 
all 16-mm sound-films available for projection were made by optical 
reduction from 35-mm original negatives. 

Later on, the cost of 16-mm film for amateur use became prohibi- 
tive, and with the improvement of films, lenses, cameras, and pro- 
jectors in 8-mm, amateur interests began to be transferred almost 
entirely to this medium. Today, the relative costs and the technical 
results of the 8-mm medium are such that we can safely say that 16- 
mm is almost exclusively a professional medium and 8-mm is almost 
exclusively an amateur medium. We must, therefore, consider the 
question of 16-mm emulsion position in the light of the fact that 
16-mm sound-films produced from 16-mm originals are almost entirely 
of commercial origin. 

Emulsion Position in 35 -Mm Practice. When 35-mm negative is 
threaded in a camera, the emulsion of the film faces the camera lens. 
When this negative after development is contact-printed, the emul- 
sion of the print faces and is in contact with the emulsion of the 
negative. When the print that results is then threaded in a 35-mm 
projector, the emulsion on the print is opposite that of the emulsion 
on the negative, and, therefore, the emulsion of the print faces the 
light-source of the projector. This emulsion position of the print is 
called the 35-mm "standard emulsion position." When 35-mm film 
is used, therefore, its application, so far as emulsion position is coti- 



Aug., 1942] 16-MM EMULSION POSITION 125 

cerned, is quite simple. Essentially, all original 35-mm black-and- 
white picture is taken as negative, and prints are made by contact- 
printing upon positive raw film. Despite the rapid and continued 
growth of the industry, even including the introduction of sound, the 
35-mm medium still remains a negative-positive medium in which 
films are still developed and printed in exactly the same way they 
have been handled for some forty years or more. 

Our 35-mm standards recognize the standard emulsion position as 
the one and only emulsion position to be used in 35-mm release prints. 
Once a projector has been installed in a theater and adjusted to give 
the proper size of picture on the screen and to scan the sound-track 
in the proper manner, no further adjustment is required except for 
maintenance. Any 35-mm film received for projection will automat- 
ically be in proper focus for both the picture and the sound ; there are 
no non-standard emulsion position 35-mm films released for commer- 
cial use. 

Since negative-positive processing is and always has been the only 
processing generally available in 35-mm, it was only natural that the 
jargon of the industry would take account of that fact. It is not un- 
common, therefore, for the terms, "original" and "negative" to be 
used interchangeably in 35-mm slang, and many who are beginning 
to work in both media after having worked previously only in the 
35-mm medium, attempt to carry over the interchangeability of 
terms into 16-mm, where the use in that manner is definitely in 
error. 

The Early History of 16 -Mm Reversal Film. About 1924, the East- 
man Kodak Company made available to the American market a 
16-mm film product that is still unknown in commercial 35-mm 
films reversal. In order to encourage amateur movie making, it 
was necessary to eliminate, if possible, the second piece of film, the 
print, in order to reduce the cost of the product to the user. 

Reversal had, commercially, two important advantages. The 
same piece of film was returned to the customer that the customer sent 
to the company for processing (which avoided alibis on the part of the 
customer), and at the same time, the second piece of film normally 
necessary, that is, the print, did not have to be made. 

Reversal was recognized, in our 16-mm standards only by the cap- 
tion, "In the projector, the base (not emulsion) side of the positive, 
made ... by the reversal process . . . faces the light source." It is 
interesting to note that even at this late date, duplicate reversals 






126 W. H. OFFENHAUSER, JR. [J. S. M. P. E. 

are given no formal consideration whatever in our dimensional stand- 
ards, despite the fact that they became commercially important as 
early as 1931. 

Reversal and Kodachrome What They Are. Reversal (in the 
broadest sense) may be most simply defined as a direct positive. 
When properly handled, black-and-white reversal film is one of the 
finest materials available for use today as a 16-mm picture original. 
It always produces a reduction in grain size; the larger grains are 
most affected by the first, or negative, exposure that the film re- 
ceives, but these larger grains are later removed in the subsequent 
bleaching operation, leaving only the smaller grains of the emulsion 
to make up the final image. A study of the relative graininess of 
optical reductions from 35-mm negatives in comparison with original 
reversal as a 16-mm original material appeared in the JOURNAL in 
November, 1940, in a paper entitled "Commercial Motion Picture 
Production with 16-Mm Equipment," by J. A. Maurer. 

Kodachrome goes a step farther; the final image in Kodachrome is 
a grainless dye image. Just as in the case of reversal, the silver emul- 
sion in Kodachrome is bleached out after the initial exposure and 
development; dyes form the image in development after the second 
exposure. Practically, Kodachrome has one other advantage: its 
development is usually less contrasty than that of reversal. This, 
too, makes for an improved original. 

Kodachrome as an original 16-mm material has another advantage 
that can hardly be overlooked in these days of emergency. It is 
possible to print excellent Kodachrome sound duplicates at the same 
time excellent black-and-white prints are being made. This is pos- 
sible since the Kodachrome sound duplicates are manufactured from 
the Kodachrome original and a positive black-and-white sound-track, 
while the black-and-white prints are made from a black-and-white 
duplicate negative of the picture and from the original negative sound- 
track. 

Early History of 3 5- Mm Sound- Film. When sound-film was com- 
mercially introduced in 1929, it was forced to adapt itself to the nega- 
tive-positive procedure of the 35-mm picture. It is obvious that if 
the sound is to appear on the same piece of film with the picture in the 
combined print, both picture and sound must be developed in the 
same developer solution. This sound -recording procedure was 
pinned down into a negative-positive procedure to conform with the 
processing of the picture. The production of the release prints from 



Aug., 1942] 16-MM EMULSION POSITION 127 

the original negatives was quite satisfactory so long as the sound 
negative could be made in relatively long lengths without splices. 

In the early stages, scenes were quite long, often as long as two 
minutes. As the sound motion picture grew, the length of the indi- 
vidual scene became shorter and shorter until now the average length 
of a scene is considerably less than one-tenth of what it was in 1929. 
For this and other reasons, a demand for re-recording and for lip 
synchronization grew, all of which implied a large number of scenes 
per reel, and, consequently, a large number of splices in the original 
sound negative. It was only logical, therefore, that the industry 
would attempt to produce some sort of direct sound positive which, 
when re-recorded for release purposes, would eliminate one copying 
step between the original sound-track and the release print. (Direct 
positive to re-recorded negative to release print.) 

In the case of sound, however, reversible film did not come to the 
rescue as it did in the case of the 16-mm picture in 1924. Another 
difficulty had arisen which is characteristic of all silver emulsions in 
some degree that would prevent the successful application of rever- 
sible film in this manner. For want of a better description, it will be 
called here the "graying" effect. In the JOURNAL are to be found 
numerous papers on the subject of envelope and other types of film 
distortion in which this graying effect plays an important part. We 
have been counter-acting this distortion effect in the negative by at- 
tempting to produce an equal and opposite effect in the print by the 
choice of proper exposure and of proper development of the print. 
In this procedure, we have been more or less successful, and this 
method is the one that is preferred commercially today. 

An attempt was made, however, to record directly on fine-grain posi- 
tive stock with the recording system optics and the electrical ele- 
ments so modified as to produce a direct positive. The distortion in 
the direct positive was considered low enough in certain cases to be 
ignored. For purposes of identification, we shall call this form of 
direct positive recording "optical reversal" to distinguish it from 
"chemical reversal." The term "optical reversal," while not strictly 
correct, will be assumed to include the recording of variable-density 
direct positives such as variable-density toe-recorded sound-film. 

The successful direct positives required film of the fine-grain, high- 
resolving-power type. Due to the difficulty of obtaining enough 
exposure and for other reasons, direct positives have not been com- 
mercially adopted. The customary 35-mm procedure is to record 



128 W. H. OFFENHAUSER, JR. fj. S. M. P. E. 

the original sound as a negative, edit it, then make a 35-mm sound 
positive and then re-record that 35-mm sound positive using the 
resulting sound negative for making the release prints. 

Early History of 16-Mm Sound-Film. After the initial failure in 
1930 of 16-mm sound negatives made by re-recording, direct 16-mm 
sound remained dormant for a number of years. A 16-mm sound 
camera put in its appearance in 1932, operated by the single-system 
method. So far as sound was concerned, this unit fell heir to the poor 
resolution encountered in the commercially unsuccessful re-recording 
attempts of 1930. One important factor in the failure of this unit 
was that the film used did not have satisfactorily high resolution since 
it was a negative-type film. 

It was evident that the only commercially practicable solution in 
16-mm would be double-system sound-recording just as it had been 
the solution in 35-mm sound-recording. It was not long afterward 
that 16-mm double-system sound-recorders were put on the market. 
Plans were being formulated for their marketing as early as 1936. 

Current Status of Direct 16-Mm Sound. By far the largest volume 
of direct 16-mm sound is produced by the double-system method 
with negative-positive processing of the sound-track. Studies have 
been made of the application of reversal to sound, but it has been 
concluded so far that what we have called the "graying" effect pre- 
vents any reasonable use of the distortion cancellation technic such 
as we daily find so valuable in negative-positive 16-mm commercial 
operations. This factor becomes more important as the number of 
copying operations required between the original and the release 
print increases; this is especially true of variable-area sound, with 
which there has been more commercial experience in the 16-mm 
medium. 

Kodachrome Sound Duplicating and Its Implications. At the pres- 
ent time, practically all sound to be duplicated on Kodachrome is 
recorded as a negative, and a black-and-white positive track print is 
made from that negative. It is the positive sound-track print that is 
used in the printing operation to the combined duplicate. For the 
purpose of this discussion, it makes little difference whether the 
original sound-track is recorded originally on 35-mm film or on 16-mm 
film. 

It seems likely that one of the reasons why so few direct sound posi- 
tives can be used for Kodachrome printing is that the distortion due 
to the graying effect is excessive. This does not mean, however, that 



Aug., 1942] 16-MM EMULSION POSITION 129 

all positives are afflicted with the same handicap ; positives of the dye 
type seem to be less affected by this peculiar characteristic of silver 
emulsions. Considerable development and research work has been 
carried on in this direction that seems to hold promise for the future. 

The 16-Mm Emulsion Position Question. It can be seen from the 
foregoing that the 16-mm emulsion position question can not ade- 
quately be dealt with in a casual manner. Reversal and Koda- 
chrome, which do not exist commercially in 35-mm motion pictures, 
are used almost to the exclusion of negative in 16-mm for picture 
originals. Kodachrome sound duplicates, of which there are possibly 
some quarter of a million feet per month or more currently used in 
16-mm, do not exist in 35-mm at all. These distinctions between 35- 
mm and 16-mm would certainly seem to merit some form of standards 
recognition. 

A few years aeo, the author submitted to the Standards Committee 
of the Society a memorandum classifying the methods of producing 
16-mm release-prints then in use. Sixteen-mm sound-prints may 
be produced by a wide variety of methods. They may be classified as 
follows : 

Class 1. Film Width of Original 

(a) Originals supplied on 35-mm. 

(b) Originals supplied on 16-mm. 

(c) A combination of both 35-mm and 16-mm, either 

(1) 35-mm picture with 16-mm track, or 

(2) 16-mm picture with 35-mm track. 

Blow-ups from 8-mm picture to 16-mm are not uncommon even now, and it is 
possible that this procedure will grow. 

Class 2. Sound Recording Processes 

(a) Variable-density. Full-width, squeeze, push-pull; with or without noise 

reduction. 

(b) Variable-area. Unilateral, bilateral, duplex, others (such as multiple). 

(c) Combinations of variable-area and variable-density (not in common use). 

Class 3. Processing Methods 

(a) Negative-positive processing (where the image black-and-white aspect is 
reversed in printing). 

(6) Second exposure or direct positive processing (a positive from a positive, 
such as a reversal dupe ; a Kodachrome dupe. 

(c) Single exposure processing (where the image is reversed optically or elec- 
trically, as in the case of a sound-track master record made for direct 
playback, one exposure and one processing). 

Combinations of these classes are not at all uncommon ; our standards, if com- 
prehensive, should encompass any reasonable combination of any or all of the 



130 W. H. OFFENHAUSER, JR. [j. s. M. P. E. 

preceding classes, methods, or sizes. At the present time, we are especially con- 
cerned with: 

(1} Reduction of 35-mm negatives, both picture and sound, to 16-mm. 

(2) Combinations of a 16-mm original with a 35-mm original (such as Koda- 
chrome or reversal picture and 35-mm negative track, or 35-mm negative 
picture with 16-mm negative track). 

(5) Direct 16-mm where the picture original is either a 16-mm negative, rever- 
sal, or Kodachrome, and the sound-track is an original 16-mm negative. 

The Problem of 16- Mm Prints from 35 -Mm Originals. Whenever 
16-mm prints are needed from 35-mm originals, one important ques- 
tion must be answered before the sound is recorded if the final result 
is to be of optimum quality. It must be definitely decided whether 
35-mm prints are to be made at all; if they are, it is manifestly im- 
possible to record a single sound-negative that is suitable both for 35- 
mm prints and for 16-mm reduction prints due to the difference in the 
recording equalizing required. The reason is readily apparent if we 
examine the equipment situation. 

If a Hollywood studio sound-track is run upon a 35-mm sound 
system that meets the specifications of the Academy of Motion Pic- 
tures Arts & Sciences, the result is standard. The reason is that the 
recording is so made as to reproduce most effectively upon equipment 
with the Academy characteristic. 

Such a negative, if optically reduced without fidelity loss, would 
also operate most satisfactorily with equivalent equipment having 
Academy characteristics. The characteristics under such conditions 
are: 

CO The slit width should be 1.3 mils multiplied by 36/90 (the film-speed 
ratio) or one-half a mil. One manufacturer of projectors, Eastman Kodak, manu- 
factures equipment with that slit width ; no other major manufacturer does. 

(2) The resolution of the 16-mm film should be in the inverse ratio of the film 
speeds, or 90/36 = 2.5. Fine-grain 16-mm film accurately controlled will readily 
approximate this requirement when compared with regular 35-mm positive as 
commercially processed. 

(3) A really good optical printer designed to expose fine-grain 16-mm film with 
the proper chromatic and intensity characteristics, will "hold up" in our comparison 
with the usual 35-mm non-slip printers printing upon regular 35-mm positive. 

(4) The amplifiers, obviously, should be at least the equal in signal-to-noise 
ratio and in distortion, to 35-mm booth equipment. This is no chore as there is 
on the market a wide variety of amplifiers of reputable make and performance 
suitable for the purpose. Needless to say, the best 16-mm projector amplifiers, 
while somewhat inadequate, are not too far wide of the mark. 

(5) Last but not least, the loud speakers must be comparable with those con- 



Aug., 1942J 16-MM EMULSION POSITION 131 

sidered in connection with the 35-mm Academy characteristic Unfortunately, 
this is probably one of the worst 16-mm bottlenecks. While we cling to the idea 
that the performance of a 16-mm loud speaker is immaterial just so long as a frail 
ninety-pound schoolteacher can lift said loud speaker, we might as well give up 
our search for 16-mm sound-quality in projection. In order to obtain performance 
somewhat comparable, the loud speaker should have the following character- 
istics: 

(a) Directional radiation not much more than a sixty-degree lateral spread 

and a thirty-degree vertical spread. This is readily obtained with a suit- 
able horn. 

(b) Good efficiency ; also obtained if a suitable horn is used. 

(c) Good transient characteristics on speech; also obtained if a suitable horn 

is used. 

A loud speaker, to meet the above requirements, would have to be a directional 
horn; the present flat baffle type of equipment is hopelessly inadequate. 

Unfortunately, it is not possible to obtain, as regular articles of 
commerce, all five of the items exactly as enumerated above. 

A Commercial Solution to the Problem of 16 -Mm Prints from 35- Mm 
Originals. There are several obvious commercial steps in the solu- 
tion of the problem of good 16-mm reproduction from 35-mm orig- 
inals. They are: 

(1) Re-record the sound-track using a 16-mm equalizing characteristic. If this 
record is made by direct 16-mm on high-resolving-power yellow-dye film exposed 
in a good 16-mm sound-recorder through the proper filter, 6-db equalization 
broadly tuned at 5500 cycles is sufficient for excellent films. A 6000-cycle low- 
pass filter may prove of advantage. 

(2} Make a 35-mm fine-grain lavender of the picture, and then make a fine- 
grain dupe negative of that lavender. 

(3) Make the 16-mm combined prints on fine-grain film, printing the sound 
with an optical one-to-one sound printer (contact sound printing is inadequate). 

(4) Use a commercial projector that will meet the specifications set forth by 
the Non-Theatrical Equipment Committee in the July, 1941, issue of our JOURNAL, 
"Recommended Procedure and Equipment Specifications for Educational 16-mm 
Projection." A Bell & Howell Utility Filmosound will substantially meet the 
requirements. 

(5) Use a good loud speaker such as the Bell & Howell Orchestricon. When 
projecting, set it in such a position that its horn radiates directly to the audience. 

(6) For safety's sake (projection requirements are rarely properly analyzed), 
use a matte screen. 

The Current Status of 16-Mm with Regard to Emulsion Position. 
When a IG-mm sound-film is properly threaded in a IG-mm pro- 
jector, the emulsion of the film may face the screen (which position 
is called the "standard" position), or it may face the projector light- 



132 W. H. OFFENHAUSER, JR. [j. s. M. P. E. 

source (the "non-standard" position). Any well-designed projector 
of today should be capable of projecting either "standard" or "non- 
standard" prints. 

All 16-mm combined prints from 35-mm originals such as those 
previously described have the "standard" emulsion position. The 
best quality 16-mm black-and-white combined prints from 16-mm 
originals also have the "standard" emulsion position. At the present 
time the output of such prints amounts to several million feet of film 
per month. 

Most 16-mm combined Kodachrome duplicates have the "non- 
standard" emulsion position. At the present time, the output of such 
prints amounts to something like a quarter to a half million feet per 
month. When it is considered that the cost of a 400-foot combined 
duplicate in Kodachrome is approximately $50, whereas a similar 
black-and-white print costs but $9, it becomes even more apparent 
that the existence of Kodachrome sound duplicates is entitled to con- 
sideration from projector manufacturers especially. 

When projecting Kodachrome duplicates, it is found necessary to 
refocus the picture ; the emulsion position is non-standard. It would 
seem obvious, therefore, that if the picture must be refocused in order 
to be clearly seen, the sound optics must likewise be refocused if the 
sound is to be clearly heard. The surprising feature in the projection 
of Kodachrome sound duplicates is that more than 90 per cent of the 
projectors in use are not equipped to refocus the sound optics for 
proper projection. Only one manufacturer of 16-mm sound projectors 
has so far included this feature on most of his sound projectors as 
standard equipment; only one other manufacturer has offered such 
a feature as optional on all his machines at slight additional cost. 

It is well to remember that, with present-day sound optics, there is no 
satisfactory compromise fixed adjustment suitable for both "standard" 
emulsion position black-and-white prints and "non-standard" emul- 
sion position Kodachrome duplicates. The usual adjustment is in 
the form of a small lever with two definite settings. 

There are other sources of "non-standard" emulsion position film 
today, but the quantity in use in such that they are of minor impor- 
tance from the standpoint of volume. It is quite possible that, with 
a wider distribution of 16-mm apparatus immediately after the War, 
they will acquire additional importance. 

The Question of Optical Picture Printing. In all the foregoing, it 
may rightfully be charged that the possibility of optical printing of 



Aug., 19421 H>-MM EMULSION POSITION 133 

16-mm picture has been ignored in this discussion, and only contact 
printing of 16-mm picture has been presumed. This charge is quite 
true and it will no doubt continue to be true, at least for the dura- 
tion of the War. If optical printing of picture is as desirable as many 
think, why is it that the 35-mm theatrical industry which spends 
millions of dollars on its productions and on their exhibition still 
makes all its release prints by contact printing? Sixteen-mm costs 
must be kept low, very low in comparison with 35-mm costs, and it 
would seem that if there is to be a trend in the direction of optical 
picture printing, 35-mm should lead the way. Sixteen-mm costs 
must be lower than 35-mm costs ; if optical printers are at all worth 
using, their disadvantages must be overcome ; their operating speeds 
are very low and their first costs and operating costs very high. 

While the present War emergency continues, it seems unlikely that 
any reputable optical manufacturer can be induced to divert his 
energies to the marketing of suitable optics for a 16-mm picture 
printer that will correct emulsion position at a price to compare in a 
practicable way with the present price for a contact printer. 

Conclusion. At the present time, it seems clear that neither emul- 
sion position can be successfully dispensed with as a standardizing 
matter. The dollar value of the non-standard prints produced is now 
considerable when compared with that of the standard prints. For 
the duration of the War, at least, both emulsion positions will con- 
tinue to be of indispensable importance. 

TECHNICAL APPENDIX 

16-Mm Sound Negatives. Direct 16-mm sound negatives are usually recorded 
upon a high-resolving power yellow-dyed film exposed through a blue filter. Two 
windings of raw stock are available, Winding A and Winding B. The rules for 
their use are: 

USE WINDING A for sound negatives for 

(1) Kodachrome sound duplicates with the sound-track printed from a fine-grain 

sound-track print of the sound negative. 

(2) Combined prints from original reversal or Kodachrome picture made from a 

fine-grain duplicate negative of the picture and from the sound negative. 
(5) Combined prints from 35-mm picture negative and 16-mm sound negative. 

USE WINDING B for sound negatives for 

(1) Combined prints from original picture negative and 16-mm sound-track nega- 

tive. 

(2) Fine- grain sound-track prints to be used for re-recording. 



134 W. H. OFFENHAUSER, JR. 

16-Mm Picture Original. In 16-mm picture original and in all steps where 
sound does not appear on the film, use double perforated film to avoid laboratory 
and other handling difficulties. 

Preparation Rules. (1) In all cases, use only double perforated leader with 
doubly perforated film, and single perforated leader with single perforated film. 

(2) In all cases, splice in the leader with base to emulsion so that the same 
side of the film is up on the leader, as on the picture proper. 

(5) In all sound-films without picture, mark the head of the film H and the tail 
of the film with a T to avoid confusion due to emulsion position. 

Emulsion Position of Prints. Prints with "Standard" emulsion position re- 
sult from: 

(1) Original 16-mm black-and-white reversal to intermediate negative 

to print (the 16-mm sound negative is recorded upon film of A wind- 
ing). 

(2) Original 16-mm Kodachrome to intermediate black-and-white nega- 

tive to black-and-white print (the 16-mm sound negative is recorded 
upon film of A winding). 

(3) Optical reduction from 35-mm negatives. 

Prints with "Non-Standard" emulsion position result from: 

(7) Original 16-mm negative to print (the 16-mm sound negative is recorded 
upon film of B winding). 

(2) Original 16-mm Kodachrome to 16-mm Kodachrome duplicates (the 
16-mm sound negative is recorded upon film of A winding. Sixteen-mm 
track negative to 16-mm black-and-white track print to Koda- 
chrome duplicate of sound). 

A well planned picture takes into account the emulsion position of the release 
print and how it is to be obtained quite as much as it does the photographic images 
to be recorded on the film. 

After the presentation of the above paper at the Convention, a demonstration 
film, made as described, was projected with an arc projector on an 8 X 12-ft. 
screen through a sound system of the type described, in order to demonstate the 
theatrical quality of the sound and picture. 



THE PRODUCTION OF INDUSTRIAL MOTION PICTURES 
LLOYD THOMPSON** 



Summary. The production of industrial sound motion pictures is similar to 
production in the major studios. Limited budgets mean that certain short-cuts must 
be taken but the final screen results must be such that the audience is not aware of the 
limited budget. If satisfactory results are to be obtained, close cooperation is required 
between the director who has his special problems and the technical department which 
also has its special problems. 

The paper lists a number of these problems and also discusses what can be expected 
of industrial producers. 

Today industrial motion picture producers are being called upon 
to produce a greater variety of shows than ever before. Many of the 
productions needed call for the industrial (and I say industrial for 
the lack of a better term) technic. To an industry which, of neces- 
sity, has been mainly concerned with entertainment production, this 
comparison of industrial and entertainment technic may be of interest. 

The industrial producer of today must have three things, and it 
matters not whether he is using the 35-mm method or the direct 
16-mm method of production. These three things are: (1) the 
personnel, (2) the experience, (3) the proper facilities. 

If he has the above qualifications he must do two things to do busi- 
ness at a profit. (1) He must solve his own technical and production 
problems so that he can make a finished production both technically 
and artistically. (2) He must give his customers true value, and 
leave them with the feeling they have enjoyed a pleasant and profit- 
able experience. 

The production of industrial sound motion pictures is in many 
ways carried on the same as the production of straight dramatic 
shows. In other ways it is different. Probably the first big differ- 
ence is in the amount of money that the producer has to spend. With 
enough money many of the problems of any business disappear. It 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received April 
UM, 1942. 

** The Calvin Company, Kansas City, Mo. 

135. 



136 L- THOMPSON [j. s. M. p. E. 

is the solving of many of these problems without spending too much 
money that makes the life of an industrial producer interesting and 
at times hectic. 

A million dollar budget is rather common for a Hollywood produc- 
tion. The average cost of an "A" feature is nine hundred thousand 
dollars. If someone allots one hundred thousand for an industrial 
it becomes news and is given wide publicity. More often industrial 
shows are made for three or four thousand dollars. Seventeen or 
eighteen thousand dollars is an excellent price for an industrial in 
color and sound. 

On the other hand the buyer of any picture expects a show that 
will train his employees, sell his product, or make the public look with 
favor on his product. In other words it must do the job for which 
it was intended. To do this it must be at least reasonably well 
photographed. It must be edited in a logical sequence and should 
unfold on the screen in at least a fairly smooth manner. This, of 
course, calls for good planning and good direction. 

To turn out a job that will fulfill all the requirements means close 
cooperation between every department from the sales department 
who sold the picture to the shipping clerk who must see that the 
prints are shipped in time, quite often to meet deadlines. This 
means the proper personnel with the experience that will enable them 
to work together most efficiently. An organization producing indus- 
trial shows works most efficiently if the different members of the 
group understand the problems involved in the various departments 
of the organization. 

The sales department must sometimes work for years to sell a 
single picture. This means that a long line of prospects must always 
be in the process of being sold. Equally important the salesman for 
industrial pictures must thoroughly understand the whole production 
business of making a show. If not he can easily oversell. We like 
to tell the story about a salesman who did not understand the pro- 
duction business. This salesman once wrote a scene into a minimum 
priced script, showing ten thousand Macedonian soldiers in a V 
formation. The scene would have been about two feet long. In 
this case the production was not sold and so that problem did not 
have to be solved. A smart salesman is the one who does not even 
mention the impossible scenes. 

Many things have been sold by salesmen that the producer was 
unable to deliver, but the ethical producer wants to sell repeat busi- 



Aug., 1942] INDUSTRIAL MOTION PICTURES 137 

ness and is therefore careful not to promise anything he can not 
deliver. The salesman of dramatic shows might be likened to a 
salesman of ready-made suits and a salesman for an industrial pro- 
duction might be likened to a tailor. The salesman of dramatic 
shows may sell whole blocks of pictures to theater exhibitors and 
about all the customers know about them is that they will be some 
sort of entertainment. On the other hand, an industrial show must 
be made to order, and the salesman must at least know how to take 
the measurements. If the original measurement is not made right 
the chances are that the finished production will be pretty sloppy. 

We often read of the difficulties Hollywood directors have with 
authors of books that are being made into shows. In an industrial 
show this man is usually represented by someone from the advertising 
department of the client. This representative can be of great help 
and his services are badly needed to be certain that misstatements or 
inaccuracies do not creep into the final production. On the other 
hand this person can make the director's life miserable for a time un- 
less the director has enough salesmanship about him to convince the 
advertising man that certain things should be done and others should 
not. 

Many times it is the representative's first experience with motion 
pictures and he lets his enthusiasm carry him away. He may try 
to get four or five pictures into one, or he may show so much useless 
detail that the picture will be uninteresting to his audience. He may 
let the various departments of his company influence him too much 
and as a result he will want to show too much of, let us say, the 
laboratory. A good director will point out these things and they will 
be eliminated from the script. Occasionally the representative can 
not be convinced, and no one knows what may happen after that. 
It is safe to say, however, that these shows usually end up with re- 
takes, re-editing, rewritten script, usually miss the deadline, and are 
not as smooth as they should be. 

In planning the show the director and the writer must always keep 
in front of them the amount of money that can be spent in producing 
the show. Here experience counts a great deal, and without this 
experience a producer can easily lose his shirt. Most scenarios must 
not call for large expensive sets. Many times the shows are shot on 
location as a matter of fact many times they must be shot on loca- 
tion. Frequently long shots are made on location and close-ups are 
made in the studio, especially where synchronous sound is to be used. 



138 L- THOMPSON [j. s. M. P. E. 

This technic is, of course, not new or novel. The industrial producer 
must avoid using scenes that might be difficult and expensive to shoot. 
A simple set may tell the story just as well and if the audience has 
not seen the expensive set they will not miss it. This does not mean 
that locations must not be established. They must. Optical effects 
are especially useful in establishing such locations. 

The industrial script writer and director must always be thinking 
of his actors. His budget is limited and this must limit the amount 
of high-priced talent that he can use. On the other hand he must use 
talent that can give a fairly good performance or the final result will 
be distinctly unsatisfactory. 

Since the director may have to use talent that is not as experienced 
as some of the stars, it means more rehearsals and sometimes more 
takes. Direct 16-mm production helps here because more takes can 
be made without worrying too much about raw-stock costs. If the 
director must limit his number of takes because of the cost of raw 
stock, the finished production will probably not be smooth. In 
color this item becomes even more important. 

A director of industrial shows must interpret a script differently 
from the way a director of dramatic shows would interpret it. With- 
out the proper experience a director is likely to become too dramatic 
and many times when an industrial show becomes too dramatic it 
stands out as something distinctly "phoney." Of course this char- 
acteristic can quite easily be created by an inexperienced script 
writer. An "Elmer Blurp" type of presentation is funny on the radio 
or in an entertainment production, but this same sort of technic used 
in an industrial show would probably appear utterly ridiculous. 

After the picture has been sold and the script written and put into 
shape for production, the industrial producer then has the problem 
of getting the picture on the film so that it will be good both artisti- 
cally and technically. 

To do a successful job the picture must have sound that is clear and 
easily understood. Volume level and tone quality should be uniform. 
It may need music and sound effects. It may need synchronous 
sound taken at different locations. If all these things are to fit to- 
gether smoothly it will almost always need re-recording. The 
photography must also be smooth and easy-flowing. If an editor is 
to make a smooth picture he must be able to insert at the proper 
places in the photography wipes, fades, dissolves, and so on, that may 
have come from stock or from some other show, or may have been 



Aug., 1942] INDUSTRIAL MOTION PICTURES 139 

made in different parts of the world. To put these effects into an 
original is sometimes impossible and nearly always more costly than 
doing it in the laboratory. This means that the producer must have 
some method of making these effects either in his own laboratory or 
be able to purchase them from an outside laboratory. The buyer of 
an industrial and his audience are used to all these little refinements. 
They compare an industrial show with what they see in their local 
theaters. It is therefore almost necessary that the present-day indus- 
trial producer be able to give all these little refinements or enhance- 
ments in a picture costing perhaps less than ten thousand dollars, 
although the theatergoer compares it with one that cost a hundred 
thousand dollars. 

As we have already stated the director has a limited amount to 
spend on talent. Usually the better the talent the easier it is to 
record, photograph, and direct. This means that the industrial 
producer must always work to get the best quality he is capable of 
making in his sound. Most of the sound that he does record will be 
played on 16-mm projectors in the field. This means that the quality 
must be kept good if the final results in the field are to be satisfactory. 
Since top-flight talent can not always be used, this means a double 
handicap for the sound recording technician doing an industrial. I 
believe that most of us would be amazed at some of the sound that 
is regarded as satisfactory in the theaters were it to be taken and 
optically reduced to 16-mm and then played on the ordinary 16-mm 
projector in the field. It would be almost as enlightening as if the 
commercial producer were allowed to set up his equipment on the 
best Hollywood stage with a cast of stars and then play his track 
back only in a big theater. He would probably be amazed at his own 
quality. 

During the past few years a number of people have been surprised 
at the quality obtained in direct 16-mm recording. In a number of 
cases direct 16-mm has shown up better than 35-mm reduced. There 
are several things that might account for this technically. It is also 
partly due to the experience of the sound man making these tracks. 
He knows the unfavorable conditions under which most of these 
sound-tracks will be played and he has learned to compensate for 
some of the deficiencies that must be expected in the field. It is 
much easier to make passable sound when it is to be played back on 
the best of equipment. The problem of the industrial producer is to 
make sound that is at least passable on almost any equipment en- 



140 L. THOMPSON [j. s. M. p. E. 

countered in the field. This is no reflection on the manufacturer of 
the equipment because a great many of the difficulties in the field are 
no fault of his, and as many of the people in the field gain more experi- 
ence many of these difficulties will be eliminated. 

There are many camera problems in industrial production. Fre- 
quently shots must be made in factories and on production lines. 
These must be made without stopping the work, or with the least 
amount of waste time. This means that it is not always possible to 
use as many lights as are wanted or it means that the lights can not 
always be placed where the cameraman would like to have them. In 
color it means that angles may have to be picked that will keep day- 
light from being mixed with Mazda. Here again the 16-mm pro- 
ducer has an advantage because he can use much smaller equipment 
and angles that would be impossible with larger equipment. In 
shooting by the direct 16-mm method, the producer of color pictures 
has still another advantage. It is a simple matter to shift from day- 
light to Mazda type Kodachrome. The Mazda type Kodachrome 
can be used to photograph under photofloods, which are easily obtain- 
able and which do not need any special color correction filters. Ex- 
perience has shown that the film is not too critical to color-tempera- 
ture, and even under rather unsatisfactory conditions good color 
pictures can be obtained without too much difficulty. Here again 
the experience of the crew is all-important. 

There is the problem of music for industrial productions. Music 
is a comparatively simple matter when you can go out and hire some- 
one to write a score for the picture and hire an orchestra to play it. 
This method produces excellent results but it also increases the cost 
of the production to such an extent that a great many minimum- 
priced industrials or even medium-priced industrials are not able to 
put it into their regular budget. The industrial producer has solved 
this in several different ways. There are stock music tracks he may 
use. There are stock transcriptions available to him, some on a free 
basis and some on a royalty basis. However, it is often very difficult 
to find the proper music in this library material. There is also at 
least one organization that will produce musical tracks on special 
order at a comparatively low price. 

In the past few years a number of producers have used the elec- 
tronic organ as background music. This has been fairly successful, 
but music that has been made by this method seems to show up 
"wows" rather easily, and unless the projectors in the field are quite 



Aug., 1942] INDUSTRIAL MOTION PICTURES 141 

free from these wows the music may be objectionable when it gets 
into the field. There is still another solution. We have found that 
the regular pipe organ such as the one formerly used in most theaters 
records very well. It also re-records very successfully, and if the 
producer has available an organist who knows how to get the most 
out of the pipe organ a great many different types of music can be 
played that will produce almost any mood the producer may desire. 
It has been found that music made in this manner does not seem to 
show up the wows nearly so badly as some other types of music. 

Furthermore, if the industrial producer can record special music 
for each individual reel, it simplifies the production problems con- 
siderably. Once the music has been arranged it can then be recorded 
directly onto the film in synchronism with the picture. This sound- 
track can then be re-recorded with the voice, sound-effects, and so on. 
If all the music is on one track, only one channel of the amplifier 
needs to be tied up, and it is much easier to mix it smoothly than if 
the music is coming from a number of different sources that must be 
cued very carefully. Since the industrial producer must always be 
thinking about time and cost, this is important. 

A few industrial producers own their own laboratories for develop- 
ing their original film, making their first prints and in many cases 
making their release prints. If a producer does not own his own 
laboratory he should use care in picking such a laboratory and this is 
especially true if he is working in direct 16-mm. If the operations 
of an industrial producer are extensive enough, it will undoubtedly 
be to his advantage to own his own laboratory because he will be able 
to do certain things that are almost impossible to get from any com- 
mercial laboratory. This is no reflection on the commercial labora- 
tories, who are doing a very good job in general, but it quite fre- 
quently happens that a producer wants something special. This may 
take a great deal of explaining and sometimes a considerable amount 
of experimenting to get. If the producer owns and operates his own 
laboratory mainly for the benefit of his own productions, he will be 
much more willing to try something special once in awhile. I think 
we can almost say, then, that an industrial producer must have every- 
thing a major studio has, only on a smaller scale and designed to 
operate as economically as possible. 



FIFTY-SECOND SEMI-ANNUAL MEETING 

OF THE 
SOCIETY OF MOTION PICTURE ENGINEERS 



HOTEL PENNSYLVANIA, NEW YORK, N. Y. 
OCTOBER 27th-29th, INCLUSIVE 

OFFICERS AND COMMITTEES IN CHARGE 

EMERY HUSE, President 

E. ALLAN WILLIFORD, Past-President 

HERBERT GRIFFIN, Executive Vice-President 

W. C. KUNZMANN, Convention Vice-President 

A. C. DOWNES, Editorial Vice-President 

ALFRED N. GOLDSMITH, Chairman, Local Arrangements Committee 

SYLVAN HARRIS, Chairman, Papers Committee 

JULIUS HABER, Chairman, Publicity Committee 

]. FRANK, JR., Chairman, Membership Committee 

H. F. HEIDEGGER, Chairman, Convention Projection Committee 

Reception and Local Arrangements 

ALFRED N. GOLDSMITH, Chairman 



R. B. AUSTRIAN 
L. A. BONN 
M. R. BOYER 
J. C. BURNETT 
F. E. CAHILL, JR. 
A. S. DICKINSON 
W. E. GREEN 
J. A. HAMMOND 
M. HOB ART 



J. FRANK, JR. 
G. FRIEDL, JR. 



L. W. DAVEE 
P. C. GOLDMARK 
R. F. MITCHELL 



C. F. HORSTMAN 

L. B. ISAAC 
E. W. KELLOGG 

J. H. KURLANDER 

P. J. LARSEN 
J. A. MAURER 
P. A. McGuiRE 
O. F. NEU 

J. A. NORLING 



WM. H. OFFENHAUSER, JR. 

W. M. PALMER 

H. RUBIN 

V. B. SEASE 

T. E. SHEA 

E. I. SPONABLE 

J. H. SPRAY 

R. O. STROCK 

H. E. WHITE 



Registration and Information 

W. C. KUNZMANN, Chairman 



E. R. GEIB 

F. HOHMEISTER 



H. K. MCLEAN 
P. K. SLEEMAN 



Hotel and Transportation 

O. F. NEU, Chairman 



W. M. PALMER 
P. D. RIES 
C. Ross 



J. A. SCHEICK 
F. C. SCHMID 

E. S. SEELEY 



142 



H. A. GILBERT 
G. GIROUX 



M. R. BOYER 
J. C. BURNETT 
P. C. GOLDMARK 
ALFRED N. GOLDSMITH 



FALL MEETING 

Publicity Committee 

JULIUS HABER, Chairman 

SYLVAN HARRIS 
C. R. KEITH 

Luncheon and Banquet 

D. E. HYNDMAN, Chairman 

]. A. HAMMOND 

O. F. NEU 

W. H. OFFENHAUSER, JR. 

M. W. PALMER 



143 



P. A. McGuiRE 
F. H. RICHARDSON 



E. I. SPONABLE 
J. H. SPRAY 
R. O. STROCK 
H. E. WHITE 



MRS. M. R. BOYER 
MRS. A. S. DICKINSON 
MRS. J. FRANK, JR. 
MRS. G. FRIEDL, JR. 
MRS. P. C. GOLDMARK 



F. CAHILL, JR. 

T. H. CARPENTER 
L. W. DAVEE 

G. E. EDWARDS 
J. K. ELDERKIN 



Ladies Reception Committee 

MRS. D. E. HYNDMAN, Hostess 



MRS. H. GRIFFIN 
MRS. J. A. HAMMOND 
MRS. P. J. LARSEN 
MRS. O. F. NEU 
MRS. W. H. OFFENHAUSER, 
JR. 



MRS. P. D. RIES 
MRS. E. I. SPONABLE 
MRS. R. O. STROCK 
MRS. H. E. WHITE 
MRS. E. A. WILLIFORD 



Projection Committee 

H. F. HEIDEGGER, Chairman 



W. W. HENNESSY 
J. J. HOPKINS 
C. F. HORSTMAN 
L. B. ISAACS 
A. L. RAVEN 



F. H. RICHARDSON 

P. D. RIES 

J. E. ROBIN 

H. RUBIN 

R. O. WALKER 



Officers and Members of New York Projectionists Local No. 306 

HOTEL RESERVATIONS AND RATES 

Hotel Rates. The Hotel Pennsylvania extends to SMPE delegates and guests 
the following special per diem rates, European plan : 

Room with bath, one person $3.85-$7.70 

Room with bath, two persons, double bed $5. 50-18.80 

Room with bath, two persons, twin beds $6.60-19.90 

Parlor suites: living room, bedroom, and bath $10.00, 11.00, 13.00. 

and 18.00 

Reservations. Early in September room-reservation cards will be mailed to the 
members of the Society. These cards should be returned to the hotel as promptly 
as possible to be assured of desirable accommodations. Reservations are subject 
to cancellation if it is later found impossible to attend the meeting. 

Registration. The registration headquarters will be located on the 18th floor 
of the Hotel at the entrance of the Salle Moderne, where most of the technical 



144 FALL MEETING [J. s. M. P. E. 

sessions will be held. All members and guests attending the meeting are expected 
to register and receive their badges and identification cards required for admission 
to all sessions. 

TECHNICAL SESSIONS 

Technical sessions will be held as indicated in the Tentative Program below. 
The Papers Committee is assembling an attractive program of technical papers 
and presentations, the details of which will be published in a later issue of the 
JOURNAL. 



FIFTY-SECOND SEMI-ANNUAL BANQUET AND INFORMAL GET-TOGETHER 

LUNCHEON 

The usual Informal Get-Together Luncheon for members, their families, and 
guests will be held in the Roof Garden of the Hotel on Tuesday, October 27th, at 
12:30 P.M. 

The Fifty-Second Semi- Annual Banquet and dance will be held in the Georgian 
Room of the Hotel on Wednesday evening, October 28th, at 8:00 P.M. Pres- 
entation of the Progress Medal and Journal Award will be made at the banquet, 
and the officers-elect for 1943 will be introduced. The evening will conclude with 
dancing. 

LADIES' PROGRAM 

Mrs. D. E. Hyndman, Hostess, and members of her Committee promise an 
interesting program of entertainment for the ladies attending the meeting, the 
details of which will be announced later. A reception parlor will be provided for 
the Committee where all should register and receive their programs, badges, and 
identification cards. 



MISCELLANEOUS 

Motion Pictures. The identification cards issued at the -time of registering will 
be honored at a number of New York de luxe motion picture theaters listed there- 
on. Many entertainment attractions are available in New York to out-of-town 
delegates and guests, information concerning which may be obtained at the Hotel 
information desk or at the registration headquarters. 

Parking. Parking accommodations will be available to those motoring to the 
meeting at the Hotel garage, at the rate of $1.25 for 24 hours, and in the open lot at 
75 cents for day parking. These rates include car pick-up and delivery at the 
door of the Hotel. 

Golf. Arrangements may be made at the registration desk for golfing at 
several country clubs in the New York area. 

Note: The dates of the 1942 Fall meeting immediately precede those of the 
meeting of the Optical Society of America at the Hotel Pennsylvania, New 
York, N. Y., to be held on October 30th and 31st. 

The Convention is subject to cancellation if later deemed advisable in the na- 
tional interest. 



Aug., 1942] 



FALL MEETING 



145 



TENTATIVE PROGRAM 

Tuesday, Oct. 27 

9: 00 a.m. Hotel Roof; Registration. 

10: 00 a.m. Salle Moderne; Business and Technical Session. 
12: 30 p.m. Roof Garden; SMPE Get-Together Luncheon for members, their 
families, and guests. Introduction of officers-elect for 1943 and 
addresses by prominent members of the motion picture industry. 
2 : 00 p.m. Salle Moderne; Technical Session. 
8:00 p.m. Museum of Modern Art Film Library; Technical Session. 

Wednesday, Oct. 28 

9:00 a.m. Hotel Roof; Registration. 

9: 30 a.m. Salle Moderne; Technical sessions. 

1 2 : 3 p. m. Luncheon Period . 

2: 00 p.m. Salle Moderne; Technical session. 

8:00 p.m. Georgian Room; Fifty-Second Semi-Annual Banquet and Dance. 

Thursday, Oct. 29 

9: 00a.m. Hotel Roof; Registration. 
10:00 a.m. Salle Moderne; Technical Session. 
12: 30 p.m. Luncheon Period. 

2 : 00 p.m. Salle Moderne; Technical Session. 

8:00 p.m. Salle Moderne; Technical Session and Convention adjournment. 

Note: Any changes in the location of the technical sessions and schedules of 
the meeting will be announced in later bulletins and in the final program. 

W. C. KUNZMANN, 

Convention Vice- President 



S. M. P. E. TEST-FILMS 



These films have been prepared under the supervision of the Projection 
Practice Committee of the Society of Motion Picture Engineers, and are 
designed to be used in theaters, review rooms, exchanges, laboratories, 
factories, and the like for testing the performance of projectors. 

Only complete reels, as described below, are available (no short sections 
or single frequencies). The prices given include shipping charges to all 
points within the United States; shipping charges to other countries are 
additional. 



35-Mm. Visual Film 

Approximately 500 feet long, consisting of special targets with the aid 
of which travel-ghost, marginal and radial lens aberrations, definition, 
picture jump, and film weave may be detected and corrected. 

Price $37.50 each. 

16-Mm. Sound-Film 

Approximately 400 feet long, consisting of recordings of several speak- 
ing voices, piano, and orchestra; buzz-track; fixed frequencies for focus- 
ing sound optical system; fixed frequencies at constant level, for de- 
termining reproducer characteristics, frequency range, flutter, sound- 
track adjustment, 60- or 96-cycle modulation, etc. 

The recorded frequency range of the voice and music extends to 6000 
cps. ; the constant-amplitude frequencies are in 11 steps from 50 cps. to 
6000 cps. 

Price $25.00 each. 

16-Mm. Visual Film 

An optical reduction of the 35-mm. visual test-film, identical as to 
contents and approximately 225 feet long. 
Price $25.00 each. 



SOCIETY OF MOTION PICTURE ENGINEERS 

HOTEL PENNSYLVANIA 

NEW YORK, N. Y. 



JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

VOLUME XXXIX SEPTEMBER, 1942 

CONTENTS 

PAGE 

Report of the Projection Practice Sub-Committee of 
the Theater Engineering Committee: Projection 
Room Plans 149 

Motion Picture Laboratory Practices 

J. R. WILKINSON 166 

A Modern Music Recording Studio M. RETTINGER 186 

Production of 16-Mm Motion Pictures for Television 
Projection R. B. FULLER AND L. S. RHODES 195 

Current Literature 202 

Fifty-Second Semi-Annual Meeting, Hotel Pennsyl- 
vania, New York, N. Y., October 27th-29th, Incl. 204 

Society Announcements 208 

(The Society is not responsible for statements of authors.) 



JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

SYLVAN HARRIS, EDITOR 

Board of Editors 

ARTHUR C. DOWNES, Chairman 

JOHN I. CRABTREE ALFRED N. GOLDSMITH EDWARD W. KELLOGG 

CLYDE R. KEITH ALAN M. GUNDELFINGER CARLETON R. SAWYER 

ARTHUR C. HARDY 

Officers of the Society 

*President: EMERY HUSE, 
6706 Santa Monica Blvd., Hollywood, Calif. 

* Past-President: E. ALLAN WILLIFORD, 

30 E. 42nd St., New York, N. Y. 
* Executive Vice-President: HERBERT GRIFFIN, 

90 Gold St., New York, N. Y. 
**Engineering Vice-President: DONALD E. HYNDMAN, 

350 Madison Ave., New York, N. Y. 
*Editorial Vice-President: ARTHUR C. DOWNES, 

Box 6087, Cleveland, Ohio. 
** Financial Vice-President: ARTHURS. DICKINSON, 

28 W. 44th St., New York, N. Y. 
* Convention Vice-President: WILLIAM C. KUNZMANN, 

Box 6087, Cleveland, Ohio. 

* Secretary: PAUL J. LARSEN, 

1401 Sheridan St., N. W., Washington, D. C. 
* Treasurer: GEORGE FRIEDL, JR., 
90 Gold St., New York, N. Y. 

Governors 

*MAX C. BATSEL, 501 N. LaSalle St., Indianapolis, Ind. 
**FRANK E. CARLSON, Nela Park, Cleveland, Ohio. 

*JOHN G. FRAYNE, 6601 Romaine St., Hollywood, Calif. 

*ALFRED N. GOLDSMITH, 580 Fifth Ave., New York, N. Y. 
**EDWARD M. HONAN, 6601 Romaine St., Hollywood, Calif. 

*I. JACOBSEN, 177 N. State St., Chicago, 111. 
**JOHN A. MAURER, 117 E. 24th St., New York, N. Y. 

*LOREN L. RYDER, 5451 Marathon St., Hollywood, Calif. 



* Term expires December 31, 1942. 
** Term expires December 31, 1943. 



Subscription to non-members, $8.00 per annum; to members, $5.00 per annum, included 
in their annual membership dues; single copies, $1.00. A discount on subscription or single 
copies of 15 per cent is allowed to accredited agencies. Order from the Society of Motion 
Picture Engineers, Inc., 20th and Northampton Sts., Easton, Pa., or Hotel Pennsylvania, New 
York, N. Y. 

Published monthly at Easton, Pa., by the Society of Motion Picture Engineers. 

Publication Office, 20th & Northampton Sts., Easton, Pa. 

General and Editorial Office, Hotel Pennsylvania, New York, N. Y. 

Entered as second-class matter January 15, 1930, at the Post Office at Easton, 

Pa., under the Act of March 3, 1879. Copyrighted, 1942, by the Society of Motion 

Picture Engineers, Inc. 



V 



REPORT OF THE PROJECTION PRACTICE 
SUB-COMMITTEE 

OF THE 

THEATER ENGINEERING COMMITTEE 
PROJECTION ROOM PLANS 

The projection room plans that follow constitute the third revision 
of the original plans published by the Committee in August, 1932. 
The two prior revisions were made in October, 1935, and November, 
1938. Such revisions are necessary from time to time in order to 
keep pace with the changes and developments in the art and practice 
of projecting sound motion pictures and to assure that the projection 
room is so planned that it will permit maximum efficiency of operation 
of the equipment installed within it. The Committee urgently 
recommends the adoption of these Recommendations by all architects 
and builders in designing and remodeling projection rooms so that 
greater uniformity of construction and greater efficiency in projection 
will exist in the future. 

In following these Recommendations, proper authorities should in 
all cases be consulted for possible deviations therefrom as may be 
required for conformance to local rulings. All fire-protection require- 
ments specified or referred to herein are in accordance with the 
National Board of Fire Underwriters and the National Electric code, 
which should be consulted for details. 

Projection space facilities shall consist of (1) the projection room 
proper, (2) film rewind and storage space, (3) a power equipment 
room, and (4) a lavatory. 

PROJECTION ROOM PROPER 

(1.1) Construction. The projection room shall be of fire-resistant 
construction throughout and shall be supported by or hung from 
fire-resistant supports. The projection room shall have a minimum 
height of 8 feet. The width and depth of the projection room shall 
be governed by the quantity and kind of equipment to be installed 
within it, and also by whether the film-rewinding and film-storage 

149 



150 



THEATER ENGINEERING COMMITTEE [j. s. M. p. E. 







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FIG. 1 ( Upper). Layout with separate rewind room. 

FIG. 2 (Center). Layout with rewind bench and storage cabinet at 
end of room. 

FIG. 3 (Lower). Layout with rewind bench and storage cabinet 
behind projectors. 



Sept., 1942] PROJECTION ROOM PLANS 151 

facilities are to be incorporated in a separate room or be a part of the 
projection room proper. 

The minimum width of the projection room, for one projector, 
when film-re winding facilities are provided for in a separate room, 
shall be not less than 8 feet. For each additional projector, spot- 
light, stereoptican, or floodlight machine shall be added an additional 
6 feet in width. The minimum depth of the projection room, when 
film-rewind and storage facilities are provided for in a separate room, 
shall be not less than 10 feet (Fig. 1). 

When film-rewinding and storage facilities are incorporated within 
the projection room proper, which may be desirable under some 
conditions, the minimum width of the projection room when the 
film-rewinding and storage facilities are placed in line with the pro- 
jectors, shall be not less than 16 feet for one projector. For each 
additional projector, spotlight, stereoptican, or floodlight machine, an 
additional 6 feet in width shall be added. When film-rewinding and 
storage facilities are within the projection room proper and placed in 
line with the projectors, the minimum depth of the projection room 
shall not be less than 10 feet (Fig. 2). 

When film-rewinding and storage facilities are incorporated within 
the projection room proper and are located to the rear of the pro- 
jectors, the minimum width of the projection room for one projector 
shall be not less than 8 feet. For each additional projector, spot- 
light, or floodlight machine, an additional 6 feet in width shall be 
added. When film -re winding and storage facilities are incorporated 
in the projection room proper, and placed at the rear of the projectors, 
the minimum depth of the projection room shall be not less than 12 
feet (Fig. 3). 

Great care should be exercised in selecting the film-rewinding and 
storage facilities layout that will be most efficient for each particular 
theater. Efficient operation requires that the screw shall be in view 
of at least one member of the working projection room staff whenever 
a picture is being projected to the screen. 

Generous consideration should be given to all probable future needs 
for additional projection room space. 

The projection room proper shall be so located with respect to the 
screen that the vertical projection angle shall not exceed 14 degrees. 
Since the ideal projection angle is one of zero degrees, it is recom- 
mended that every consideration be given to keep the projection 
angle at as near the ideal as possible. Optical axes of the projectors 



152 THEATER ENGINEERING COMMITTEE [j. s. M. P. E. 

shall be five feet apart. When two projectors are used, the optical 
axes shall be equidistant from the centerline of the auditorium; when 
three projectors are used, the optical axis of the center projector shall 
be on the centerline of the auditorium. Motion picture projectors 
shall be given preference over stereopticans, spotlights, or floodlight 
machines, for installation nearest the centerline of the auditorium. 

(1.2) Floor. The floor of the projection room shall be sufficiently 
strong and solid for the load it is to bear. A minimum strength of 
floor construction of 200 pounds per square-foot plus the dead weight 
of the construction proper is recommended. A generous factor of 
safety should be allowed. A type of floor construction recommended 
consists of (1) a reinforced concrete floor-slab not less than 4 inches 
thick, (2) a tamped cinder fill above the floor-slab not less than 4 
inches thick, and (3) a troweled cement finish above the cinder fill, 
not less than 2 inches thick. Items (2) and (3) have been provided in 
order to accommodate concealed electric conduits, which should be 
installed prior to placing the fill and finish. The cinder fill of the 
projection room floor may be eliminated where there is a plenum 
space beneath the projection room area proper, and which area is 
available for the running of conduit. 

(1.3) Walls and Ceiling. The projection room walls shall be built 
of brick, tile, or plaster blocks plastered on the inside with 3 /Vinch 
cement or acoustical plaster, or all concrete. The core of the wall 
shall be not less than 4 inches thick. When plaster block is used, it 
shall be supported upon steel framework. All electrical conduits 
shall be in masonry chases in the wall construction so that they shall 
not project beyond the finished plaster line (see Sec. 6.1). In all 
cases, the inside surface of the front wall shall be smooth and without 
structural projections. The ceiling shall be constructed of 4-inch 
concrete slabs or pre-cast concrete, or of 3-inch plaster blocks sup- 
ported by a steel structure and plastered on the inside with 3 / 4 -inch 
cement plaster or acoustical plaster. All electrical conduits in the 
ceiling shall be concealed (see Sec. 1.10). 

(1.4) Doors. A door shall be provided at each end of the projection 
room. Doors shall be not less than 2 feet 6 inches wide and shall be 
6 feet 8 inches high. Doors shall be approved fire-doors of a type 
suitable for use in corridor and room partitions (Class C openings, as 
defined in the Regulations for Protection of Openings in Walls and 
Partitions'), shall be self-closing, swinging outwardly, and shall be kept 
closed at all times when not used for egress or ingress. It shall be 



Sept., 1942] PROJECTION ROOM PLANS 153 

possible at all times to open either door from the inside merely by 
pushing it. Door jams shall be made of steel. 

(1.5) Windows. Where a projection room is built against the 
exterior wall of a structure, one or more windows may be provided in 
the wall. Window construction shall be entirely of steel, and the 
glass shall be of the shatter-proof type. Adjustable metal louvres 
or equal means shall be used to exclude direct light. Extreme caution 
should be taken to prevent dirt and dust from entering the projection 
room area through windows opening directly to the outdoors. 

(1.6) Portholes. (General) Two portholes shall be provided for 
each projector, one through which the picture is projected, known as 
the "projection port" (see Sec. 1.7), and the other for observation of 
the picture screen by the projectionist, known as the "observation 
port" (see Sec. 1.8). 

The observation port shall be located above and to the right of the 
projection port. The distance between the horizontal centerlines of 
the projection port and the observation port shall be 15 inches; the 
distance between the vertical centerlines of the projection port and 
the observation port shall be 21 inches. 

Where separate spotlight, stereopticon, or floodlight machines are 
installed in the same projection room with motion picture projectors, 
not more than one port opening (see Sec. 1.9) for each machine shall 
be provided for both the projectionists' view and for the projection 
of the light, but two or more such machines may be operated through 
the same port. 

(1.7) Projection Ports. The finished ports shall be 10 inches by 10 
inches, measured on the inside wall. 

The required height of the centerline of the projection port from 
the finished floor varies with the make and the design of the projection 
and sound equipment to be used, and also with the vertical projection 
angle. The manufacturers of the equipment being installed should be 
consulted for these dimensions. In no case shall any part of the 
projector be less than 4 inches from the front wall of the projection 
room. Table I lists two constants for various angles of projection 
which, when substituted in the formula, will permit calculating the 
height of the centerline of the port from the finished floor level when 
certain dimensions of the projector are known. 

(1.8) Observation Ports. The finished observation port shall be not 
greater than 200 square-inches in area, measured on the inside wall of 
the projection room. A recommended size for the observation port 



154 THEATER ENGINEERING COMMITTEE [J. S. M. p. E. 

is 14 inches wide and 12 inches high, when measured on the inside wall 
of the projection room. 

(1.9) Other Ports. All other ports, such as for spotlight, stereop- 
ticon, or floodlight machines, shall be as small as practicable and in 
no case shall exceed 7 l /z square-feet in area per machine. The size 
and location of these ports will, of course, be determined by the types 



TABLE : 

Method of Locating Projector Port 
h = H + rA - DB 

Projection 

Angle 
(Degrees) A B 

1.00 0.00 

2 1.00 0.04 

4 1.00 0.07 

6 1.01 0.11 

8 1.01 0.14 

10 1.02 0.18 

12 1.02 0.21 

14 1.03 0.25 

16 1.04 0.29 

1 1.05 0.33 

20 1.06 0.36 

22 1.08 0.40 

24 1.09 0.45 

26 1.11 0.49 

28 1.13 0.53 

30 1.16 0.58 

H is the height of the center of the projector pivot from the floor; r is the 
radial distance of the optical centerline above the center of the pivot; D is the 
distance of the center of the pivot from the front wall of the projection room; 
<t> is the angle of projection; and h is the required height of the center of the port 
from the floor of the projection room. Select the values of A and B corresponding 
to the angle of projection, and substitute in the formula. 



of such machines to be used. These dimensions should be obtained 
from the manufacturers of such machines. 

(1.10) Acoustic Treatment. It is recommended that an approved 
fireproof acoustical material be applied to the walls above a height of 
4 feet from the floor, and on the ceiling of the projection room, to 
reduce the transmission of noise into the auditorium and to reduce 
projector and machine noise within the projection room proper. 




Sept., 1942] PROJECTION ROOM PLANS 155 

REWIND ROOM 

(2.1) Construction. The rewind room, if separate from the pro- 
jection room proper, shall be of fireproof construction. It shall have 
a minimum area of 80 square-feet (Fig. 1). 

(2.2) Floor. (See Sec. 1.2.) 

(2.4) Doors. The door shall be an approved fire-door of a type 
suitable for use in corridor and room partitions (Class C openings, as 
defined in the Regulations on Protection of Openings in Walls and 
Partitions), shall be arranged to be self-closing, swinging outwardly, 
and shall be kept closed at all times when not used for egress or in- 
gress. Door jams shall be made of steel. 

(2.6) Ports. Where the rewind room is adjacent to the auditorium, 
an observation port shall be provided through which the picture 
screen may be seen from within the rewind room. This port shall be 
at the same height from the finished floor as the observation ports in 
the projection room proper (see Sec. 1.6). 

(2.8) Observation Port. (See Sec. 1.8.) 

(2.9) Other Ports. An observation window shall be provided 
between the projection room and the rewind room', consisting of a 
fixed fireproof frame and polished plate wire glass. This window 
shall be not more than 200 square-inches in area, and shall have its 
horizontal centerline 5 feet from the finished floor level. 

(2.10) Acoustic Treatment. (See Sec. 1.10.) 



POWER EQUIPMENT ROOM 

(3.1) Construction. The room shall be fireproof and shall be con- 
structed in accordance with Sections 1.2, 1.3, 2.4, and 1.10. The 
size shall be governed by the quantity and kind of equipment to be 
installed. Generous consideration shall be given to probable future 
needs. 

(3.2) Special Equipment. It is recommended that wherever rotary 
power equipment, such as motor-generator units, is employed hav- 
ing an input rating in excess of 15 horsepower, such equip- 
ment be installed remote from the theater auditorium, such as in the 
basement, to prevent acoustical hum or mechanical vibration from 
reaching the auditorium section of the theater. Extreme caution 
should be taken to insulate properly all rotary equipment that may 
be located at the projection room level, regardless of size, against the 
possibility of excess mechanical vibration and hum. All arc-supply 



156 THEATER ENGINEERING COMMITTEE [j. S. M. p. E. 

equipment located in the power- equipment room, including projection 
arc rheostats, shall be at least 4 feet from all sound- amplifier units. 



LAVATORY 

(4.1) Construction. The lavatory shall be provided with running 
water and modern sanitary facilities, with tiled floor and built-in, 
flush- type medicine closet. 

EXITS 

(5.1) General. Two exits shall be provided, one at each extreme 
end of the projection room, permitting direct and unobstructed 
egress (see Fig. 1 and Sec. 1.4). Any stairs forming part of these 
{exits should have risers not in excess of 8 inches and a minimum 
tread of not less than 9 inches. The distance between walls in any 
section of the exits shall not be less than 36 inches. Winding or 
helical stairs should be avoided. A platform at least equal in length 
to the width of the door shall be provided between the door and the 
first riser. Neither ladders, scuttles, nor trap-doors shall be used as 
means of entrance or exit. 

CONDUITS AND CIRCUITS 

(6.1) Locations and Sizes. Locations and sizes of conduits and 
wiring for projection control and sound equipment units are deter- 
mined by the quantity, types, and designs of the equipment to be 
installed. Manufacturers of the equipment should be consulted with 
regard to proper layout and sizes of conduit and wiring systems before 
floors, walls, and ceilings are finished (see Sees. 1 .2 and 1 .3) . Conduits 
shall in all cases be concealed, and all boxes shall be oi the flush type, 
when located in the floors, walls, or ceiling. Conduits terminating 
in the floor shall extend 6 inches above the finished floor level. The 
wiring and conduit layout shall be in accordance with the National 
Electrical Code. Wiring shall be provided for the following usual 
circuits, and wiring for special or additional equipment shall also be 
provided : 

(1) Projector mechanism 

(a) Drive motor 
(6) Change-overs 

(c) Pilots 

(2) Projectors, spotlights, and floodlight machines 

(d) Arc supply 

(6) Arc ballast rheostats 



Sept., 1942] PROJECTION ROOM PLANS 157 

(5) Sound equipment 
(a) A-c supply 
(6) Amplifier controls and power-supply units 

(c) Loud speaker circuits 

(d) Ground wire 

(e) Sound heads 

(4) Projection room lighting 

(a) General 
(&) Emergency 

(5) Theater auditorium lighting 

(a) Regular 
(6) Emergency 

(6) Projection room ventilating system 

(a) Normal 
(6) Emergency 

(7) Projector ventilating system 

(a) Normal 

(8) Miscellaneous 

(a) Stage curtain control 

(b) Telephones 

(c) Buzzers and signal system 

(d) Receptacles 
() Clock outlet 

(6.2) Power- Supply to Equipment. Where line-voltage variations 
are greater than == 3 per cent, the local power company should be re- 
quested to correct the condition. In cases where it is impossible 
normally to maintain steady line-voltage to the equipment, suitable 
voltage regulators shall be used. 

LIGHTING 

(7.1) Projection Room Lighting. Approved indirect or semi-indirect 
ceiling fixtures of the vapor-proof type shall be used for general illu- 
mination, and should be arranged to be lighted from either the normal 
or emergency lighting circuit. A single reel-light of the vaporprool 
type with wire guard shall be centrally located on the projection 
room ceiling, and shall be equipped with sufficient approved cord to 
allow extension of this reel-light to all parts of the projection room 
proper. 

Individual ceiling fixtures of the vaporproof type shall be installed 
at the operating side of each projector spotlight, stereopticon, or 
floodlight machine. All projection room lighting fixtures shall be 
equipped with keyless sockets and shall be controlled from wall 
switches. All lights in the projection room and associated rooms 



158 THEATER ENGINEERING COMMITTEE [J. S. M. p. E. 

shall be properly shaded so as to prevent light from entering the 
auditorium through the porthole openings. 

(7.2) Rewind Room. An approved vaporproof ceiling fixture shall 
be installed for general illumination. A drop-light or wall-bracket 
fixture of an approved vaporproof type shall be provided over the 
rewind table. These lights shall be controlled from a wall switch 
independently of any lights in the projection room proper. 

VENTILATION 

(8.1) Projection Room. The projection room proper shall have the 
following ventilating facilities : 

(a) Carbon arc exhaust 

(&) Fresh air supply 

(c) Projection room exhaust, including an emergency exhaust 

The carbon arc exhaust system shall be a positive mechanical 
exhaust system independent of all other ventilating systems of the 
theater. Each projector, spotlamp, stereopticon, or floodlight ma- 
chine, if of the carbon arc type, shall be connected by a flue to a 
common duct, which duct shall lead directly out of doors. Reduction 
of the ventilation to each projector as required shall be accomplished 
by means of a local damper between the projector lamp-house and 
the projection room ceiling, and in addition, by means of the damper 
on the lamp-house proper if provided. 

This exhaust system shall be operated by an exhaust fan or blower 
having a capacity of not less than 50 cubic-feet of air per minute for 
each arc lamp connected thereto. The exhaust fan or blower shall be 
electrically connected to the projection room wiring system and shall 
be controlled by a separate switch, with pilot lamp, within the pro- 
jection room proper. There shall be at no time less than 15 cubic- 
feet of air per minute through each lamp-house into this exhaust 
system. Fig. 4 shows the general arrangement. The ducts shall be 
of non-combustible material, and shall be kept at least 2 inches from 
combustible material or separated therefrom by approved non- 
combustible material, not less than 1 inch thick. 

The fresh-air supply to the projection room shall consist of not less 
than two intake ducts located at or near the floor and at opposite 
ends of the room, and shall be connected into the main air-supply 
ducts of the building. There shall be no connection between this 
air-supply system and any of the exhaust systems of the projection 



Sept., 1942] 



PROJECTION ROOM PLANS 



159 



room. It is recommended that gravity-operated dampers connected 
to the emergency port-hole release system be installed in the fresh-air 
intake registers to prevent smoke from entering the main theater 
fresh-air duct system, in case of a fire in the projection room area. 



u=9- *;.'""" 




FIG. 4. Equipment ventilation system: blower capacity 400 cu-ft 
per min; minimum air movement through lamp houses with blower idle, 
15 cu-ft per min. 

The projection room exhaust system shall be a positive mechanical 
exhaust system having a normal capacity of not less than 200 cubic- 
feet per minute and having an auxiliary emergency capacity of not 
less than 1000 cubic-feet per minute for operation in emergency, i. e., 




FIG. 5. General and emergency ventilation system: normal blower 
capacity 200 cu-ft per min; emergency capacity 2000 cu-ft per min. 

(A) Switch and pilot lamp for normal operation, inside projection room ; 
(B) switch and pilot lamp for emergency operation, outside door of pro- 
jection room; also connected to port fire-shutter control mechanism. 

(Two or more fresh-air intakes required at or near the floor at opposite 
ends of the room.) 



fire. The ventilation system shall terminate in ceiling grilles in the 
projection room, which shall not be less than two in number. In no 
case shall this room exhaust system be connected into any of the 
ventilating systems of the theater proper. The emergency position 
of this fan shall be controlled by a switch (Fig. 5) operated auto- 



160 



THEATER ENGINEERING COMMITTEE [j. s. M. P. E 



matically by the shutter control system, when the latter is actuated 
either manually or by melting of the fusible links. This exhaust fan 




FIG. 6. Example of port shutter construction. Although this construction 
shows rivets, spot welding is preferable. 

shall be electrically connected to the emergency lighting system of 
the building. Control shall be provided for manual operation of this 



Sept., 1942] 



PROJECTION ROOM PLANS 



161 



fan from a point immediately outside the projection room proper, in 
addition to the emergency control in the shutter system. 

(8.2) Rewind room. The general ventilation of the rewind room, 
i. e., fresh-air supply and room exhaust, shall be a part of the pro- 
jection room fresh-air supply system and the projection room exhaust 
system. There shall be no connection between the projection arc 
exhaust system and any part of the rewind room ventilating system . 

Film cabinets, if of the single-compartment type shall be vented to 
the outside air by means of a gravity vent (see Sec. 12.2). 

(9.1) Port-Hole Shutters. Each port opening shall be provided with 
a gravity shutter of approved construction. The shutter and its 



I__M 




FIG. 7. One of many possible arrangements of the port fire-shutter control. 
The automatic switch operates the exhaust fan and emergency lights. 



guides shall be constructed of not less than No. 10 gauge iron and the 
shutter shall be set into the guides not less than 1 inch at the sides 
and bottom, and shall overlap the top of the port opening not less than 
one inch, when the shutter is in a closed position. Shutter guides 
shall be of welded construction, and should be built into the masonry 
of the projection room walls (Fig. 6). Shutters shall be suspended, 
arranged, and so interconnected that they will all close upon the 
operation of some mechanical releasing device or the operation of 
some fusible link, so designed to operate automatically in case of fire 
or other emergency requiring immediate and complete isolation of 
the projection room from the other portions of the building. Each 
shutter shall have its individual fusible link above it. A fusible link- 
shall be located also above each upper projector magazine which upon 



162 THEATER ENGINEERING COMMITTEE [j. s. M. P. E. 

operation shall close all the port shutters. There shall be provided 
also a suitable means for the manual release of the shutter system 
from any projector head and from a point near each door within the 
projection room. Shutters shall be free-acting. Shutters on open- 
ings not in use shall be kept closed always. It is recommended that 
shutters be closed each night at the close of the show as a daily check 
on their operation. Fig. 7 shows a recommended method for arrang- 
ing the port shutter system. All large shutters such as for spot- 
lamps, stereopticons, and floodlight machines (when used) shall be 
hung in counterweighted systems to facilitate manual operation. All 
such large shutters, however, shall be so arranged that the release of 
the regular shutter system will close the large ports also. 

(9.2) Noise Transmission. The Committee recommends the use 
of means other than glass in projection ports to prevent transmission 
of noise from the projector room to the auditorium, such as by re- 
ducing the free aperture of the port to the minimum size necessary to 
pass the projection beam, or by the use of fireproof sound-baffles. 
Observation ports shall be fitted with a good grade of plate glass set 
in metal frames at an angle to the vertical to avoid direct reflection, 
and such glass shall be easily removable from the projection room side 
for cleaning. The purpose of this glass is to reduce noise trans- 
mission into the auditorium. 

HEATING 

(10.1) General. Proper provision shall be made for heating the 
projection room. The same facilities used for heating the theater 
shall be extended to the projection room. 

PAINTING AND FLOOR COVERING 

(11.1) Painting. The color of the walls shall be olive-green to the 
height of the acoustical plaster. The latter shall be painted in 
accordance with the instructions of the manufacturer of the material, 
and preferably a dull buff color. The ceiling shall likewise be painted 
in accordance with these instructions but in a white color. All iron- 
work of the projection ports shall be covered with at least two coats 
of flat black paint. 

(11.2) Floor Covering. Where local regulations permit, the floors of 
the projection room and rewind room shall be covered with a good 
grade of battleship linoleum cemented to the floor. The floor cover- 
ing shall be laid before the equipment is installed. 



Sept., 1942] PROJECTION ROOM PLANS 163 

EQUIPMENT 

(12.1) Projection Room. All equipment to be used in the projection 
room, including the projectors, arc lamps, sound equipment, etc., shall 
be of approved type. 

All shelves, furniture, and fixtures within the projection room suite 
shall be constructed of metal or other non-combustible and approved 
material. An approved metal container shall be provided for hot 
carbon stubs. Adequate locker space for projectionists' clothing 
shall be provided. 

(12.2) Rewind Room. In the rewind room shall be provided an 
approved fireproof film-cabinet or safe, a rewind table, approved 
rewind equipment, a mechanical film-splicer, an approved film-scrap 
can, and an approved storage cabinet for film-leaders, snipes, etc. t 
used only at various intervals. 

The film-cabinet, or safe, shall be capable of holding 25,000 feet of 
35-mm film on standard reels. Doors on film-cabinets or safes shall 
be of the automatic tight-closing type, and either of the single-reel 
compartment or single-compartment type. Film-cabinets of the 
single-compartment type holding in excess of 50 pounds of film 
(10,000 feet) should be vented to the outside air by means of a gravity 
vent. The vent should not be less than 36 square-inches in area for 
each 50 pounds of film stored. This vent shall be constructed of 
non-combustible material and shall be kept at least 2 inches from any 
combustible material, or shall be separated therefrom by approved 
non-combustible material not less than one inch thick. Film- 
cabinets of the single-compartment type having a capacity of more 
than 50 pounds of film (10,000 feet) also should be equipped with an 
automatic sprinkler-head, of the 3 /4-inch size, connected to the 
theater water-supply. It is recommended that pressure at such 
sprinkler head be not less than 15 pounds. 

All tables, racks, and all furniture shall be of metal or other ap- 
proved non-combustible material, and shall be kept at least four 
inches away from any radiator or heating apparatus. Tables shall 
not be provided with racks or shelves beneath them whereon may be 
kept film or other materials. 

The film-scrap can shall have an automatic, self-closing lid, and 
shall be of approved type. It is recommended that a type designed 
to keep scrap-film immersed in water at all times be used. 

Quantities of collodion, amyl acetate, or other inflammable cements 



164 THEATER ENGINEERING COMMITTEE [J. s. M. P. E, 

or liquids kept in the rewind room for any purpose shall not exceed one 
pint. 

No stock of inflammable materials of any sort whatever shall be 
permitted within the rewind room except as mentioned above. 

Film shall be kept in the film-cabinet at all times except when it is 
being projected, rewound, or inspected. Any films in addition to 
those used for the current showing or in excess of that permitted by 
local authorities shall be kept in their original shipping containers. 
Film-leaders used occasionally may be kept in an approved cabinet 
designed for that purpose. 

All film splices shall be made with approved mechanical cutting 
and splicing machine. No hand cutting or splicing shall be per- 
mitted. 

(12.3} Fire-Extinguishing Equipment. Local authorities having 
jurisdiction with regard to fire-extinguishing equipment should be 
consulted regarding the proper types, numbers, and locations of such 
equipment. 

It is the recommendation of this Committee that fire-extinguishers 
of the carbon tetrachloride or carbon dioxide types be considered for 
use in projection rooms, as they have proved to give the most effective 
protection for the specialized equipment within the projection room. 
In addition to their being the most effective fire extinguishers, they 
do not cause the ruin of the precision equipment installed within the 
projection room proper, if it is necessary that they be used for any 
emergency. 

MISCELLANEOUS 

(13.1) "No Smoking" signs shall be posted in prominent places, 
and matches should not be carried by any employee having access 
to the projection room. 

(13.2) Operation. Motion picture projectors shall be operated by 
and shall be in charge of qualified projectionists who shall not be 
minors. A projectionist should be stationed constantly at the oper- 
ating side of a projector while it is in operation. A proper factor of 
safety in operation, as well as avoidance of imperfect operation of 
projection equipment or unjustified interruptions of service can be 
attained only by having an adequate personnel in the projection 
room. 

(13.3) Action in Case of Fire. In the event of film fire in the pro- 
jector or elsewhere in the projection or rewind room, the projectionist 



Sept., 1942] PROJECTION ROOM PLANS 165 

shall immediately shut down the projector and all arc lamps, operate 
the port shutter release at the point nearest him, turn on the audi- 
torium lights, leave the projection room immediately, and notify the 
manager of the theater or building. 

THEATER ENGINEERING COMMITTEE 

ALFRED N. GOLDSMITH, Chairman 
Sub-Committee on Projection Practice 

C. F. HORSTMAN, Chairman 

H. ANDERSON R. R. FRENCH E. R. MORIN 

T. C. BARROWS E. R. GEIB J. R. PRATER 

H. D. BEHR M. GESSIN F. H. RICHARDSON 

K. BRENKERT A. GOODMAN H. RUBIN 

F. E. CAHILL, JR. H. GRIFFIN J. J. SEFING 

C. C. DASH S. HARRIS R. O. WALKER 

A. S. DICKINSON J. J. HOPKINS V. A. WELMAN 

J. K. ELDERKIN L. B. ISAAC H. E. WHITE 

J. FRANK, JR. I. JACOBSEN A. T. WILLIAMS 

J. H. LlTTENBERG 



MOTION PICTURE LABORATORY PRACTICES* 
JAMES R. WILKINSON** 



Summary. The function of laboratory service to studio production departments 
and to the release distribution field is discussed. The size and scope of laboratory 
operations are illustrated graphically by an organization chart showing the number 
of sub-departments. These in turn are classified into three major divisions, namely, 
Control, Processing, and Maintenance. Analysis of individual department activity 
begins with the Control division, and emphasis is placed upon the recent trend toward 
more scientific approach to the problems of processing. Discussion continues with the 
Processing division, starting with negative development, and the processing method of 
each successive department is described showing the inline flow of the work for both 
studio and release print operations. Problems relating to proper mechanical and elec- 
trical maintenance are also discussed. 



The motion picture laboratory is, essentially, a service organiza- 
tion. Its operations, while of an extremely technical nature, are not 
creative in any sense of the word, and possibly because of this fact its 
efforts are unsung and little in the way of publicity has been released 
from the industry relative to its activity or its contribution to motion 
picture entertainment. Papers on the subject have been written by 
G. M. Best and F. R. Gage, and by C. L. Lootens. 1 

The scope of laboratory service normally embraces the studio pro- 
duction division, i. e., Camera, Sound, and Editorial departments; 
also the distribution division, including both Foreign and Domestic 
departments. Viewing the laboratory as a part of a major studio or- 
ganization, it is considered as a single department similar to the 
Camera, Make-up, or Art departments. Actually the laboratory is 
one of the largest of the studio units, normally employing from 150 
to 250 workers, and is itself divided into approximately twelve sub- 
departments, each with its operating foreman and a crew ranging 
from five to thirty workers. The specialized nature of the various 
laboratory operations foster this departmentalization and, under ex- 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received May 
10, 1942. 

** Paramount Pictures, Inc., Hollywood, Calif. 
166 



MOTION PICTURE LABORATORY PRACTICES 



167 



isting conditions, it is very seldom that an overlapping of depart- 
mental activities occurs. 

To assist in visualizing laboratory operating methods Fig. 1 shows 
a typical organization chart and the relationship of the various de- 
partments to the supervising personnel. While the chart is typical 
of the average laboratory, variations can and do occur within the 
individual plants. Laboratory activities seem to be naturally di- 
vided into three rather separate and distinct divisions, namely, the 
Control division, the Productive or Processing division, and the Sup- 



S<4>rinn4nt 






FIG. 1. Laboratory organization chart. 



porting or Servicing division. Within these divisions the depart- 
ments are identified as follows : 

Control Sensitometry 

Chemical 
Processing Negative Developing 

Negative Assembly 

Negative Cutting 

Printing 

Positive Developing 

Positive Daily Assembly 

Release Inspection 

Projection 

Timing 



168 



J. R. WILKINSON 



[J. S. M. P. E. 



Service Mechanical Maintenance 

Electrical 
Shipping and Receiving 

Before analyzing the various departmental functions it might be 
well to state briefly the nature of the work performed by the labora- 
tory. Fundamentally it comprises the development of exposed nega- 
tive, both sound and picture, and developing of positive rush prints 
for studio purposes; also the timing, printing, development, and 
shipment of completed prints for release distribution. The work for 



Shipping BL 
Recei 



I Negative Develop. Negative 

&. Assembly [Cutting 




FIG. 



2. Production line of daily 
release print operations. 



and 



both production and distribution divisions generally passes through 
the plant at the same time, yet the segregation of the work for the two 
divisions is rather clean-cut. Each normally follows a fairly straight- 
line method of procedure and the physical arrangement of depart- 
ments, starting with the receiving room, is so planned to route the 
work through the various operations back to the point where distri- 
bution, is effected, with a minimum amount of lost motion. Fig. 2 il- 
lustrates the progressive in-line flow of daily and release operations. 

CONTROL DIVISION 

Sensitometry Department. Yielding first place only to the sound 
department, in the technical nature of its work, the laboratory has 



Sept., 1942] MOTION PICTURE LABORATORY PRACTICES 169 

made noteworthy progress during the past few years in the more 
scientific approach to its processing problems. In the control division 
this progress has been particularly marked. Sensi tome try, actually 
the junior of all laboratory departments, has assumed a measure of 
importance undreamed of originally. It is now the function of this 
department, through countless tests and calculations, to establish the 
optimal exposure and development specifications for both negative 
and positive materials, whether for sound or picture purposes. 

The wide increase in the use of specialized emulsion coatings, plus 
the intensive research program conducted prior to the general adop- 
tion of fine-grain film, has made necessary the broadening of sensito- 
metric methods to include many tests not originally a part of classical 
sensi tome try. This, in turn, called for the development of new types 
of equipment and, as a result, the dynamic analyzer together with im- 
proved photoelectric densitometers, 2 have become two of sensi - 
tometry's most useful tools. Other equipment includes the 116 sen- 
sitometer; the microdensitometer ; a sound-reproducer with suitable 
amplifiers, filter circuits, and volume indicator; a projection micro- 
scope; and a cathode-ray oscillograph. 

It is not the intent here to go into the technical details of classical 
sensitometry. The subject has been amply covered by D. Mac- 
kenzie and by L. A. Jones. 3 However, it is appropriate to review 
here some of the present duties and responsibilities of this department. 
A partial list of its activities include the following items : 

(1) The testing of all emulsions, whether negative or positive, to determine 
their characteristics. On certain emulsions the determinations of only speed and 
contrast are sufficient; while on others, such as are used for sound recording, dub- 
bing prints, master positives, etc., a very detailed and complete analysis is made. 
In addition to density and gamma characteristics they are checked for frequency 
reponse, distortion, printer gamma, grain size, etc. 

(2) The exposure, measurement, and analysis of the 116 gamma strips to aid 
the chemical department in its chemical control. This applies to all processed 
film. 

(5) The recording of densities on all sound-track negative and the selection of 
the proper printing light to give a correct print density. 

(4) Furnish complete reports to the sound department on daily sound print N 
as well as special copies such as preview prints. These include the gamma, dens- 
ity, and dynamic test data. 

(5) The checking of variable-area sound-prints by the use of the caiuvllatum 
or cross-modulation test, 4 by frequency response and by projection microscope 
examination. 

(6) The checking of variable-density sound-prints by the use of intcnnodula- 



170 



J. R. WILKINSON 



[J. S. M. P. E. 



tion, 5 delta-db, frequency response, light-valve gamma, and projected gamma 
tests. Fig. 3 shows typical graphs for cross-modulation and intermodulation 
analyses. Areas of print densities giving minimal distortion are clearly indicated. 

(7) The checking of printer equipment for exposure, field coverage, printer 
gamma, light increment, contact, image shift, flicker, and noise introduced by 
mechanical imperfections such as worn gears, backlash, etc. 

(8) The checking of developing machine equipment for 96-cycle hum, direc- 
tional effect, and drying imperfections. 

(9) Continuous collaboration with engineers of the sound department with a 
view to constant improvement in quality or technic. 

The influence of sensitometric activity is felt throughout the labora- 
tory, but its greatest importance lies in its relation to the chemical de- 



X -MODULATION CURVE 
VARIABLE AREA 



f 





















1 








I 











\ 






5 


-\ 




S? 


j 


X 


-.>- 


~*J^,- 




. _ i~_ t'tfi- - 






PWNT DENSITY 

TYPICAL INTER-MODULATION CURVE 
FOR VARIABLE DENSITY 



FIG. 3. Typical intermodulation and cross-modulation curves for 
sound-processing control. 

partment through the establishment of specifications and processing 
tolerances that govern developing activities. 

Chemical Department. The chemical department might readily 
be termed the heart of the laboratory. It is here that all processing 
solutions originate, and are pumped and circulated through a maze 
of hard-rubber piping to the various negative and positive developing 
machines. Fig. 4 shows a general view of tanks and equipment. In 
no other department has there existed a greater opportunity for 
scientific progress. The photographic process wherein a silver halide, 
which has been exposed to light, is reduced by a developing agent is 
one of the oldest of the arts. The action itself is a simple scientific 
phenomenon that is well known, yet it sets in motion a train of 



Sept., 1942] MOTION PICTURE LABORATORY PRACTICES 171 

complex chemical reactions which, due to the volume methods of 
modern technic, affect the very foundations of our work. Dr. C. E. 
Kenneth Mees states : 6 

Until recently, photographic science tended to consist of a chaos of observa- 
tions, some of them of real value and others of very doubtful value, with little in 
the way of theories to connect them properly. It is only within the last few years 
that fact after fact has been falling into place in an ordered network. 

Just as it is the function of sensitometry to establish the complete 
range of specifications and tolerances for all developing procedure, so 




FIG. 4 General view of Chemical Department installation. 

it is the responsibility of the chemical department to establish and 
maintain chemical control over all solutions. Each developing bath, 
whether it be picture negative, sound negative, or positive, is de- 
signed for a specific purpose and is so compounded that it will produce 
the best possible quality for its particular task and do so continuously. 
Since film development is a continuous operation it is only logical that 
solution replenishment likewise be continuous and proportionate to 
the bath exhaustion occasioned by the footage volume. The detail 
of procedure and the benefits to be derived from continuous replenish- 
ment are described by H. L. Baumbach. 7 



172 



J. R. WILKINSON 



[J. S. M. P. E. 



Both developing solutions and replenishes are prepared from 
chemicals that are tested in advance for their purity. These chemi- 
cals are supplied and controlled within certain tolerances which, in 
many instances, are more exacting than C. P. limits. Water that has 
been filtered, softened, and chemically analyzed is used, and is avail- 
able hot or refrigerated as well as at room temperature. It has been 
established 8 that large volumes of footage passing through a de- 
veloping solution cause reactions that necessitate control over its 




FIG. 5. Corner of chemical storage room. 



chemical constituents; namely, hydroquinone, metol, potassium 
bromide, sodium sulfite, and the alkalies that affect the pH. Fixing 
baths likewise require control for their silver content, hardening ac- 
tion, pH, stability, and rate of fixation. These controls are funda- 
mental in nature and are based upon established chemical reactions 
during analyses. Standard solutions of iodine, silver nitrate, and 
potassium thiocyanate are used for this purpose, and H measure- 
ments are determined by the Beckman pH meter (laboratory model) 
using the glass electrode. In no sense is the system of solution con- 
trol dependent upon any particular film of any manufacturer. 



Sept., 1942] MOTION PICTURE LABORATORY PRACTICES 173 

Chemical control, due to its extreme sensitivity, makes it possible 
to narrow processing tolerances, and once these have been established 
the chemical department must maintain solutions at constant values 
for all important ingredients regardless of wide variation in film foot- 
age. Cleanliness is strongly emphasized and all solutions are care- 
fully filtered to remove the insoluble by-products of development. 
Silver from fixing baths is reclaimed electrolytically in a continuously 
replenished system. In the discard the last traces are precipitated by 
zinc. 

Occasionally sensitometric measurements will reveal a variation in 
emulsion characteristics of sufficient proportions to require modifica- 
tion of the developing solution. When this occurs, changes in concen- 
trations are performed, and the developer is modified quickly and ac- 
curately to its new standard, thus maintaining the quality of the prod- 
uct at the optimal point. 

The processing of tremendous volumes of footage, normally handled 
by a release laboratory, requires vast quantities of chemicals. Fig. 5 
shows a partial view of the supply maintained. These chemicals are 
costly and the chemical department foreman is forced by necessity to 
become somewhat cost-conscious. The first consideration in every 
laboratory is the quality of the product. The laboratory is well able 
to defend this position and can point with forceful argument to the 
fact that chemicals are the least expensive of the many ingredients 
used in the processing of pictures. However this attitude does not 
justify, nor does it make a virtue of, wastefulness. The alert 
chemical engineer observes, with no small concern, the large unused 
portion of chemicals in the average discarded solution. While a rela- 
tively new development, it is becoming increasingly the practice to 
analyze these solutions, quantitatively, for their known content. The 
solution can then be modified and made suitable for a different func- 
tion. This is but another instance of chemical control which has now 
advanced to the point where solutions may be held completely within 
specifications at all times. The photographic element enters into con- 
sideration only when emulsion characteristics require a change in 
formula balance. 

Exact developing formulas are of no great significance. This is due 
to the differences in the types of developing machine, variations in 
operating speeds, degree of turbulation, etc. However, it is possible 
to present what can be considered an average Hollywood formula for 
positive, picture negative, variable-density sound negative, and van- 



174 J. R- WILKINSON [J. S. M. p. E. 

able-area sound negative developers. The densities obtained with 
these formulas are obviously dependent upon (1) exposure, (2) de- 
veloping time, and (3) developing machine characteristics. The for- 
mulas, together with the gamma range within which they operate are 
as follows : 

Positive 

Elon 1 . 50 grams 

Hydroquinone 3 . 00 grams 

Sodium sulfite 40.00 grams 

Potassium bromide 2 . 00 grams 

H* 10.20 

Water 1.00 liter 

Gamma range 2 . 00 to 2.75 

Picture Negative 

Elon 1 . 50 grams 

Hydroquinone 2 . 50 grams 

Sodium sulfite 75.00 grams 

Potassium bromide . 50 gram 

H* 8.90 
Water 1 . 00 liter 

Gamma range . 60 to . 70 

Variable-Density Sound Negative 

Elon . 50 gram 

Hydroquinone 1 . 00 grams 

Sodium sulfite 55. 00 grams 

Potassium bromide . 25 gram 

H* 8.90 

Water 1.00 liter 

Gamma range 0.35 white-light exposure, 

to 0.85 with ultra- 
violet exposure 

Variable- Area Sound Negative 

Elon 1 . 00 gram 

Hydroquinone 10 . 50 grams 

Sodium sulfite 50 . 00 grams 

Potassium bromide 1 . 50 grams 

pH* 10.20 

Water 1.00 liter 

Gamma range 2 . 75 to 3 . 10 

* The pH values of the positive and variable-area sound developers are ob- 
tained with sodium carbonate. The negative picture and the variable-density 
sound developers are buffered solutions, and the pH values are obtained by borax 
buffered with boric acid. 



Sept., 1942] MOTION PICTURE LABORATORY PRACTICES 175 

PROCESSING DIVISION 

Negative Developing Department. In describing the work of the 
departments that were grouped earlier in the processing division, it 
seems logical to start with negative development. It is the first of 
the many operations that culminate in the final release print for ex- 
hibition. Early pioneers within the industry gave much thought to 
the development of their negatives, and the reason for this is obvious 
even under changed and modern conditions. Exposed negative repre- 
sents value, and it is not unusual for the negative of a single day's 
work on a picture to have actually cost from ten to twenty thousand 
dollars. Obviously, only trained personnel and operating equipment 
that has been perfectly maintained can be entrusted with this im- 
portant task. Guesswork is out of the question and all hazard, as far 
as is humanly possible, must be eliminated. 

Much has been written and more will be written regarding the theo- 
retical considerations of negative development. The subject is large 
in scope and productive of considerable divergence of opinion. It is 
well known that the overall gamma or contrast of the final screen print 
is the product of the negative and the positive gamma. It therefore 
follows that compensation for variation in negative gamma can be ob- 
tained by an inverse variation of the contrast of the positive bath. 
Normal picture negatives, in Hollywood, are developed within a 
gamma range of 0.60 to 0.72, and positive solutions are adjusted to 
give satisfactory screen quality at both extremes. A negative in the 
low-gamma range requires very full exposure and fairly rapid de- 
velopment. By this procedure grain size is held to a minimum; 
however, emulsion speed is proportionately reduced. These condi- 
tions may be graduated progressively over the gamma range to the 
other extreme, where exposure is held to the minimum, development 
is prolonged, grain size is increased, and the emulsion speed is fully 
utilized or even forced. Excellent results can be and are obtained by 
developing to a gamma of 0.66, which is in the center of the range. In 
a properly balanced negative solution, development to a gamma of 
0.66 permits full advantage to be taken of emulsion speed, yet de- 
velopment need not be extended to a point where grain size becomes 
objectionable. This procedure likewise has its economic advantage in 
that extremely high levels of illumination by the cinematographer are 
avoided. 

There are two schools of thought regarding negative development. 



176 J- R. WILKINSON [j. s. M. P. E. 

Certain laboratories are using what is commonly known as the test- 
system while others are developing to a constant gamma. Those us- 
ing the test-system require the cameraman to make tests for the labo- 
ratory whenever a change in set-up or an important change in light- 
ing occurs. These tests are broken out of the exposed roll of negative, 
properly identified, and developed in advance to a standard time. 
The negative developer, after examining the developed tests may, at 
his discretion, increase or decrease the development time on scenes 
that he believes could be improved by greater or lesser development. 
In developing to a constant gamma the solution is controlled to give 
constant gamma and density at a given developing time, and all nega- 
tive is developed to this standard. It is not the purpose of this paper 
either to acclaim or condemn these two systems or to argue the 
relative merits of the two systems. It is sufficient to acknowledge 
that major studio laboratories are employing both systems at the 
present time with apparently satisfactory results. 

Negatives of both sound and picture are developed on continuous 
developing machines. These machines are often identical in type, dif- 
fering only in speed of operation and nature of solution. Both density 
and gamma specifications for sound-track negative vary over a wide 
range. Specifications are affected not only by the type of recording 
system used, i. e., variable-area vs. variable-density, but also by varia- 
tions in emulsion speed, contrast, frequency response, and distortion 
characteristics of the several different fine-grain recording stocks now 
widely used. The sound department makes the decision relative to 
optimal negative processing levels, and upon being notified of these 
specifications, the laboratory adheres to them rigidly until subsequent 
tests dictate a change in levels. 

Prior to actual developing operations the machines are serviced 
and solutions are tested both analytically and by sensitometric 
strips. The negative has been made up into rolls of practical size for 
efficient machine operation, and development proceeds. On picture 
negative the time consumed, from the moment the film enters the 
developing solution until it has passed through the various stages of 
fixing, washing, and drying and is spooled on the take-up reel, is ap- 
proximately forty-five minutes. Sound negative, being a positive 
type of emulsion, requires less time in the different stages of machine 
development, and passes through the equipment in thirty-five min- 
utes. In addition to rigid solution control, temperature and humidity 
of the drying cabinets must be maintained within very close limits. 



Sept., 1942] MOTION PICTURE LABORATORY PRACTICES 177 

Temperature normally runs 80 F and relative humidity is held at 
55 per cent. 

Negative Assembling Department. Following development, the 
negative passes to the negative assembling department. Here the 
negative is broken down into individual scenes, and is carefully 
inspected for defects that may have been caused by the camera or the 
developing machine equipment. During this operation the worker 
has before him the camera or sound reports upon which all scene num- 
bers have been logged. Scenes that have been selected for printing 
are segregated from the takes on which no print is desired. The latter 
are classified as "out negative," and are carefully identified and filed 
in vaults for possible future use. The "print" takes are assembled in 
numerical continuity, and a light-card is prepared for each reel. This 
card shows the date, the production number, all scene numbers within 
the reel, and the type of raw stock to be used for printing and a col- 
umn is provided for future printing lights. 

As this operation is completed the assembled sound-track negative 
is sent to the sensitometry department, where densities are measured 
and the proper printing light is indicated on the light-card opposite 
each scene. The assembled reels of picture negative, together with 
their light-cards, proceed to the cinex testing room and the work of 
the negative assembly group is completed. 

Timing. Upon arrival of the assembled negative in the cinex test- 
ing room, each scene is carefully examined and test exposures are 
made for timing purposes. These tests, when developed and dried 
by a standard developing procedure, afford the tinier a strip of single- 
frame pictures made by a series of exposures precisely calibrated to 
parallel the light-increment steps of the printing machines. By visual 
examination of these tests over a uniformly diffused light-source of 
approximately 20 foot-candles, the timer selects the particular print- 
ing light which, in his judgment, will represent the best visual result 
on the screen. Fig. 6 shows the timer checking the cinex tests. 

Frequent discussions with cameramen are valuable to the timer in 
order that he may understand and faithfully interpret, through the 
print medium, the particular type of lighting or key of photography 
for which the cameraman or director is striving. This work approaches 
the artistic field more closely than any laboratory task and demands 
a high degree of skill, experience, and personal judgment. 

As the printing lights are selected they are indicated on the light- 
card opposite the appropriate scene number. Following printing 



178 J. R. WILKINSON [j. s. M. p. E. 

and development of the prints, the timer inspects his work on the 
screen; and if a scene has been missed widely, corrections are made 
and a reprint is ordered. Reprints are costly; thus it naturally fol- 
lows that the fewer the corrections the higher becomes the timer's 
individual reputation. 

Printing Department. The printing department is responsible for 
the printing of all positive film, whether for studio use or for release 
distribution. Beyond the fact that these two types of work must both 




FIG. 6. The positive timer selects printer lights. 



travel through a printing machine past an aperture, they have little 
in common. Production work for the studio comprises a large num- 
ber of widely varying specialized requirements, while release printing 
has been harnessed to mass production methods. Film for studio 
purposes is printed on the Bell & Howell Model D printer. These 
machines are continuous in operation and are designed for single 
printing, either sound or picture. Should composite prints be de- 
sired, the printing operation must be repeated, both negatives being 
printed to the same positive. All daily rush prints, except in rare in- 
stances, are printed on dual film. 



Sept., 1942] MOTION PICTURE LABORATORY PRACTICES 



179 



Due to the variation in negative densities normally encountered, 
it is necessary to provide a wide latitude of exposure range for printing 
purposes. This range is divided into approximately 30 steps, each 
step representing a light-increment of 10 per cent, or 0.06 in print 
density. A graph wherein printer-light increment is plotted against 
print density shows a linear characteristic. On the Model D ma- 
chines the intensity of the light-source remains constant, and the 
change in exposure value is accomplished by a variable aperture which 
is manually operated. Their normal speed is 62 feet per minute. 




FIG. 7. Battery of Bell & Howell 119 A release printers. 



The printing of release positive is a volume operation. For this 
work a number of the laboratories use the Bell & Howell Model 119A 
printers. Fig. 7 shows a typical installation. These machines are 
designed to handle quantity footage. They operate at higher speed, 
have more automatic features, and both track and picture negatives 
are printed simultaneously. Their light-increment and intensity 
parallel the values of the Model D machines. They are reversible in 
direction, and many copies are printed by simply supplying new posi- 
tive stock, the negative itself never leaving the machine. 



180 



J. R. WILKINSON 



[J. S. M. p. E. 



Each reel of release positive is accompanied through the plant by a 
work-card upon which each successive department logs a record of 
machines and personnel handling the film. This work-card origi- 
nates in the printing department; and upon completion of the printing 
operation, the printed positive is placed in a metal container, the card 
is attached, and the material passes to the developing department. 

Positive Developing Department. In the development of positive 
film, as in the printing operation, both studio and release work are 




FIG. 8(a). Film-developing machine; feed-in end. 

handled simultaneously. Here, even less discrimination exists inas- 
much as positive solutions are maintained at constant values and the 
development requirements of both types of work are identical. Seg- 
regation occurs only at the "take-off" end of the developing machine, 
where each type of material is routed to its proper department. The 
positive developing machine is very similar to that used for negative 
but, due to the volume requirements, is geared to operate at much 
higher speeds. Figs. 8(a) and (b) show general views of this equip- 
ment. A number of considerations affect the developing time of posi- 
tive film, but broadly speaking, it ranges between 2 x /2 and S 1 /^ min- 
utes. The complete span of the machine's operations requires about 



Sept.. 1942] MOTION PICTURE LABORATORY PRACTICES 



181 



30 minutes, and the close control of temperature and humidity, as 
previously mentioned in connection with negative, are likewise im- 
portant to the positive development. 

Following the development it is general practice to apply some type 
of film preservative to the prints. There are a number of film pre- 
servative processes in use, all of which are designed to protect the 
freshly developed emulsion surface from undue abrasion and damage 
as well as to lubricate the edges of the film to facilitate projection 




FIG. 8(6). Film-developing machine; take-off end. 

without emulsion pick-up. Various aspects of this subject are dis- 
cussed in a Bulletin published by The Research Council of The Acad- 
emy of Motion Picture Arts & Sciences. 9 

Daily Assembling Department. All developed prints that are to be 
used by the studio, both sound-track and picture, are routed from the 
developing machines to the daily assembling department. Here 
they are sorted as to picture, and the sound-track is synchronized to 
the picture print. Identification leaders are installed with proper 
"start-marks" to facilitate projector thread-up, and all prints are in- 
spected in a sound-projection room for both sound and picture quality. 
Following this inspection a log of scene numbers is prepared for each 



182 J. R. WILKINSON ft. s. M. p. E. 

reel, and if defects are present they are noted opposite the proper 
scenes. The reels are then delivered to the editorial department 
which arranges the screening for the producers. The material is re- 
tained in the editorial department and is used by the film editors in 
preparation of their first work-print. 

Negative-Cutting Department. As the preliminary editing is com- 
pleted and approved, the work-print together with an order for a first 
negative cut is sent to the laboratory. From the moment that print- 
ing of daily rushes is completed until a picture has received its final 
negative cut, the custody of its negative is the responsibility of the 
negative-cutting department. Here also is handled the work of break- 
ing down all reels into individual scenes. Proper identification is af- 
fixed to each scene showing production scene and code numbers, and 
all scenes are filed in large fireproof vaults. Reprints are often re- 
quired by the editorial department and the filing system must be so 
devised that, out of the many thousands of scenes on hand, any desired 
scene can be located at a moment's notice. 

The work-print received from the editors consists of a sound-track 
and a picture print; thus on a 10-reel production there are 20 reels 
of negative to be cut. Negative scenes of both track and picture are 
brought from the vaults to the cutting room and the negative cutters 
proceed to cut the negative, matching each scene to the corresponding 
scene in the work-print. As the reel is completed the scenes are 
spliced together, and each scene is notched to provide for printer-light 
changes. Light-cards are prepared for each reel showing scene num- 
bers, scene footages, descriptive data, and printer lights. 

Due to the necessary music and sound-effects that are re-recorded 
into all pictures, and to editorial changes following test previews, the 
first negative cut on a picture is never final. It is quite normal to re- 
match the negative to a new and changed work-print at least once 
or twice before approval is given for a final negative cut. Prints pre- 
pared between the first and final negative cut are for preview, censor- 
ship, and studio library purposes. These copies afford opportunities 
to both the picture-timer and the sound department for printer-light 
balancing corrections prior to release-printing operations. The final 
printing lights have therefore been checked and re-checked, thus 
bringing the inter-scene balance for both sound and photographic 
values to the optimal point. 

Release Assembling Department. The printing and development of 
release footage having been previously described, let us pass to the 



Sept., 1942] MOTION PICTURE LABORATORY PRACTICES 183 

work of the release assembling department. The material has been 
delivered to this department from the positive developing machines 
and it will be recalled that each reel is accompanied by its work-car 
which originated in the printing department. From the information 
on this work-card a small paper sticker is prepared and attached to 
the protective leader spliced to each release reel. This sticker remains 
on the reel permanently, eventually accompanying it to the exchange, 
and provides a record of all machine numbers as well as the initials of 
the workers who handled the film during its processing routine. It is 
similar to the inspection sticker found on many factory-made gar- 
ments, and provides a ready reference for checking processing records 
should a complaint be received from the field. 

Following the installation of leaders and stickers, the reels are in- 
spected by projection. All approved reels are sent to the spooling 
machine, while those wherein defects have been noted are sent to the 
reprint inspectors where reprints are ordered if required. As reprints 
are received, they are inspected and cut in, and that section of the reel 
is again checked before being released for spooling. After spooling, 
the reel is wrapped in tissue paper and placed in an individual con- 
tainer carefully marked in advance with the reel identifications. As 
the copies are completed in this manner they pass on to the shipping 
department for final packing and shipping. 

SERVICE DIVISION 

Film Shipping Department. Upon reaching the shipping depart- 
ment the completed copies are packed in fiberboard cartons. These 
cartons are manufactured to certain specifications of weight and 
strength, and conform to the requirements of The Interstate Com- 
merce Commission and The National Board of Fire Underwriters. 

Five methods of shipment are utilized by the laboratory: ocean 
freight, rail freight, railway express, air express, and parcel post. 
Packing specifications for foreign shipments vary greatly according 
to destination, and the shipping department must be thoroughly in- 
formed on all traffic requirements and regulations. Necessary docu- 
mentation for export shipments must be provided, and it is the 
responsibility of the traffic manager to see that all forms are correctly 
executed and properly certified. Under the present stringent regula- 
tions this feature has become a considerable problem, and it is not 
unusual to execute and certify as many as five sets of documents to ef- 
fect an export shipment. Domestic shipments to exchanges are rela- 



184 J. R- WILKINSON [J. s. M . P. E. 

lively simple and are normally sent by either rail freight or railway 
express. The distribution department is advised daily, by teletype, 
all the details of each day's shipments. 

Maintenance Department. To effect an uninterrupted flow of work 
through the various departments, provision must be made for proper 
and efficient maintenance of plant and equipment. This is a major 
problem common to all laboratories. Much of the equipment is of 
complex design and of high precision, requiring the services of expert 
technicians for maintenance and adjustment. Electrical circuits em- 
ployed likewise demand engineering knowledge of the highest order. 10 
A considerable proportion cf the required electrical energy must be 
generated as direct current, and the regulation of supply to the vari- 
ous power and light-source units must be accurately controlled. This 
control for printer-lamps is accomplished by electronic regulators, and 
a tolerance of 0.1 volt is maintained constantly. 

Equipment of the developing and chemical departments is subject 
to the action of chemicals and fumes, making constant care necessary 
to insure efficient operation. The proper maintenance and operation 
of a large air conditioning installation demands a thorough under- 
standing of refrigeration and humidity and temperature control, as 
well as the principles of air-washing and filtering. Cleanliness is 
vital to laboratory processing and these units must operate at maxi- 
mum efficiency at all times. 

The laboratory occupies a unique position in that a considerable 
portion of its equipment is not readily available for purchase in the 
open market. The maintenance staff must therefore be competent to 
design new equipment or to modify existing machines to effect the 
many improvements in technic that are brought to light through re- 
search and experience. 

CONCLUSION 

In conclusion it may be stated that the various natures of the many 
laboratory duties, together with departmental segregation, make the 
principles of organization and coordination of utmost importance to 
successful operation. Each department not only must function 
smoothly within itself but likewise must have an appreciation of the 
problems and efforts of the other departments, thus contributing to a 
well balanced efficiency in the overall task of service and research. 
With the importance of the technical phases of motion picture pro- 
duction well established and gaining increased recognition, the labora- 
tory takes a just pride in its contribution to this field. 



Sept., 1942] MOTION PICTURE LABORATORY PRACTICES 185 

REFERENCES 

1 LOOTENS, C. L.: "A Modern Motion Picture Laboratory," J. Soc. Mot. 
Pict. Eng., XXX (April, 1938), p. 363. 

BEST, G. M., AND GAGE, F. R.: "A Modern Studio Laboratory," J. Soc. 
Mot. Pict. Eng., XXXV (Sept., 1940), p. 294. 

8 FRAYNE, J. G., AND CRANE, G. R.: "A Precision Integrating Densitometer," 
/. Soc. Mot. Pict. Eng., XXXV (Aug., 1940), p. 184. 

* JONES, L. A.: "Photographic Sensitometry," /. Soc. Mot. Pict. Eng., XVII 
(Oct., 1931), p. 491, and (Nov., 1931), p. 695; XVIII (Jan., 1932), p. 54, and 
(March, 1932), p. 324. 

MACKENZIE, D. : "Straight-Line and Toe Recording with the Light-Valve," 
J. Soc. Mot. Pict. Eng., XVII (Aug., 1931), p. 72. 

4 BAKER, J. O., AND ROBINSON, D. H.: "Modulated High-Frequency Record- 
ing as a Means of Determining Conditions for Optimal Processing for Variable- 
Area," /. Soc. Mot. Pict. Eng., XXX (Jan., 1938), p. 3. 

6 FRAYNE, J. G., AND SCOVILLE, R. R. : "Analysis and Measurement of Distor- 
tions in Variable-Density Recording," J. Soc. Mot. Pict. Eng., XXXII (June, 
1939), p. 684. 

6 MEES, C. E. K.: "Recent Advances in the Theory of the Photographic 
Process," /. Soc. Mot. Pict. Eng., XXXVII (July, 1941), p. 10. 

7 BAUMBACH, H. L. : "Continuous Replenishment and Chemical Control of 
Developing Solutions." Presented at the 1942 Spring Meeting at Hollywood, 
Calif.; to be published in a forthcoming issue of the JOURNAL. 

8 EVANS, R. M., AND HANSON, W. T., JR. : "Chemical Analysis of an MQ De- 
veloper," /. Soc. Mot. Pict. Eng., XXXII (March, 1939), p. 307. 

BAUMBACH, H. L.: "The Chemical Analysis of Metol, Hydroquinone, and 
Bromide in a Photographic Developer," /. Soc. Mot. Pict. Eng., XXXIII (Nov.. 
1939), p. 517. 

ATKINSON, R. B., AND SHANER, V. C. : "Chemical Analysis of Photographic 
Developers and Fixing Baths," /. Soc. Mot. Pict. Eng., XXXIV (May, 1940), p. 
485. 

9 Committee on Improvement in Release Quality, Report by Film Preserva- 
tive Committee, F. L. Eich, Chairman, Tech. Bull., Res. Council Acad. Mot. Pict. 
Arts & Sci., (April 14, 1939). 

10 LESHING, M., INGMAN, T., AND PIER, K.: "Reduction of Development 
Sprocket-Hole Modulation," /. Soc. Mot. Pict. Eng., XXXVI (May, 1941), p. 475 
WILKINSON, J. R., AND EICH, F. L.: "Laboratory Modification and Proce- 
dure in Connection with Fine-Grain Release Printing," /. Soc. Mot. Pict. Eng., 
XXXVIII (Jan., 1942), p. 56. 



A MODERN MUSIC RECORDING STUDIO 

M. RETTINGER** 



Summary. This paper represents a broad analysis of a music recording studio 
recently completed at the RCA Manufacturing Co., Hollywood, Calif. Discussed 
herein are constructional details considered important toward the achievement of good 
recording conditions in the stage. In particular, the action of convex wood splays is 
considered in some detail, especially in regard to their influence on the reverberation 
characteristic of the room. 

In planning the remodeling of the local RCA scoring stage, special 
consideration was given to the preference among musicians and 
music-lovers for rooms which contain a large amount of wood panel- 
ing. This preference can be attributed largely to the ability of such 
a material to vibrate over a wide range of musical pitch, unlike a panel 
of plaster or fiber board. The energy employed to set the wood 
sheet into vibration is partly re-radiated in a manner that does not 
follow the regular law of equal angle of incidence and reflection. A 
vibrating surface, because of its size and shape, may therefore emit 
plane or cylindrical waves, although it is excited by spherical waves. 
In this sense, the walls of the band shell may also be considered to be 
an extension of the instruments an extension which, although loosely 
coupled to the sources of sound, nevertheless emphasizes many of the 
frequency components of music sufficiently to lend pleasant support 
to the music. It is the sounding board again a device that mag- 
nifies the tonal area of the instrument by creating sustaining surface 
sources in proximity to a relative point-source, or sources. 

It was deemed desirable to install such wood panels in the form of 
convex splays to secure a greater diffusion of the sound in the room. 
As is well known, the wavefront of a beam of sound reflected from a 
convex surface is considerably longer than that from an equally large 
flat surface, provided that the wavelength of the incident sound is 
small compared to the dimensions of the reflecting surface. Fig. 1 
shows this relationship graphically, and it is seen that the wavefront 

* Received April 1, 1942. 

** RCA Manufacturing Co., Hollywood, Calif. 
186 



MODERN Music RECORDING STUDIO 187 

reflected from the convex splay is, for the condition illustrated, con- 
siderably longer than the sum of the two reflected from the flat panels. 
The figure shows also the construction of the wavefronts, analogously 
to the optical case, the center of the reflected wavefront coming from 
the curved surface being one-half the radius of the convex splay 
(assuming the source is at some distance from the surface) . 

The fact that the wavefront from a convex reflector is longer tends 
also to reduce the interference effect between direct and reflected 
sound. This is illustrated in Fig. 2. Since the energy of a propaga- 
ting wavefront varies inversely with the square of ats length, the re- 
duction of the interference effect is appreciable, a factor that may 




FIG. 1. Illustrating length of reflected wavefront 
from convex splay and flat panels. 



assume considerable importance in the recording of slow-moving 
music. 

A convex splay is also excellent insurance against echoes in a room, 
particularly when it is intended to keep this surface reflective. For 
this reason, convex surfaces are helpful in providing a smoother decay 
of the sound, as well as one that is more nearly logarithmic with time, 
since the reverberation persists longer in the direction in which echoes 
occur in a room. 

One may therefore summarize the advantages of properly designed 
convex wood panels in a confined space as follows : 

(1) More uniform distribution of the sound pressure, due to the longer wave- 
front of the reflected sound, particularly pertinent for the high frequencies. 

(2) Creation of surface sources of sound, also helpful in increasing the diffusion 
of the sound in the room, and being of special importance for the low frequencies. 



188 



M. RETTINGER 



[J. S. M. P. E. 



(5) Provision of a wall or ceiling section that is more absorptive for the low 
than the high frequencies. The fact that work is being done on the panel in 
moving it, and that sound is radiated from the back as well as front, describes the 
device also as a relatively efficient low-frequency absorbent. 

(4) Reduction of interference effect between direct and reflected sound. 

(5) Production of a relatively smooth sound-decay curve. 

(6) Erection of reflective surfaces which will minimize echo. 

The use of vibrating wood panels in a room has, in the past, some- 
times given rise to a cautious consideration of the resonance qualities 
of such a construction. The uninitiated believe that a pronounced 
tone-bias is produced by such a vibrating panel. Indeed, one is fre- 




SOOWO PRESSURE. WER-FEREHCE. PRODUCED V Cwt^tX REFLECTOR 



SOURCE 




FIG. 2. Sound pressure interference effect produced 
by a flat and convex reflector. 



quently asked "What is the resonance frequency of this or that 
splay?" 

To avoid such a cautious regard of wood membranes as used in 
this room, it may be well to enumerate their resonance qualities thus : 

(1) A wood splay of the type employed has many resonance frequencies. Fig. 3 
shows the response characteristic of a splay at two points on it, randomly chosen, 
and approximately 5 feet apart. The curves were obtained by fastening a 
crystal pick-up to the two points and then exciting the splay into vibration by 
generating in the room a sound of a continuously varying warbled tone. 

(2} The resonance frequencies are not harmonically related. 

(5) The amplitude distribution is made up of the various modes of vibration. 

(4) Nodes are not sharply defined, owing to the presence of more than one 
mode. 



Sept., 1942] 



MODERN Music RECORDING STUDIO 



189 



The only pronounced resonance to which a splay of this type is sub- 
ject is that produced by the air-chamber back of it. The natural, 
low-frequency modes of vibration of this chamber, if it had been kept 
reflective, would have been transmitted into the stage in an objec- 
tionable measure. In the case where the chamber had been kept 
highly reflective, a "hang-over" effect or prolonged reverberation 
would have resulted at certain low frequencies, none of which was 
desired to have a reverberation time markedly longer than those of 
the middle or high registers, a point that will be discussed in greater 





FIG. 3. 



Response characteristic of a splay at two different points on 
splay. 



detail later. Hence the space back of the splays was kept absorbent, 
and care was taken not to permit the acoustic material to come into 
contact with the panel itself, which, to note, consisted of two quarter- 
inch sheets of plywood. Application of fiberboard or other sound- 
absorbent to the wood surface would have exerted a damping effect 
upon the natural modes of vibration of the wood membranes, which 
was not considered necessary or desirable for the purpose. 

The use of wood panels was welcome also because with their aid it 
was possible to achieve a nearly flat reverberation characteristic in 
the room. As is well known, the absorptivity of most acoustical 
materials is considerably smaller for the low than for the high fre- 



190 



M. RETTINGER 



[j. a M. P. E. 



quencies. The only way by which this condition can be reversed is 
by employing a thin material which by vibration will absorb the low 
frequencies while acting as a reflector for the highs. In order, how- 
ever, to avoid a pronounced selective low-frequency absorption it is 
desirable to vary the size and radii of these convex splays, as was done 
in this room. This condition was further improved by irregular 
bracing back of the splays. 




FIG. 4. Relation of monaural acoustic perspective and absorptivity. 



A nearly flat reverberation characteristic in this room was con- 
sidered desirable inasmuch as it was held that the determining factor 
for a recording studio is not so much the reverberation characteristic 
as what H. F. Olson terms the recorded reverberation characteristic. 
It should be said here that the term ''recorded reverberation" is be- 
lieved to be somewhat confusing, and that it might be better to speak 
of a monaural acoustic perspective when considering the ratio of re- 
flected to direct sound-energy density. Fig. 4 gives the equation for 
this ratio, which obviously has no dimensions, but merely states how 
much more reflected than direct sound exists at any point in the room. 
It is this ratio that gives to the recorded sound the impression of 



Sept., 1942] 



MODERN Music RECORDING STUDIO 



191 



depth and, indeed, an impression of reverberatoriness, without 
actually giving a measure of reverberation time in seconds. 

The reason for attaching so much importance to the monaural 




Jo * -a 



FIG. 5. Reverberation characteristic of RCA scoring stage. 







FIG. 6. Plan and elevation of the room. 



acoustic perspective is that the microphone represents but one ear. 
As is well known the reverberation in a room appears considerably 
longer when observed with but one ear than when observed with both 



192 



M. RETTINGER 



[J. S. M. P. E. 



ears. The reason for this lies in an unconscious suppression of re- 
flected sound, which appears to the ear as undesirable in the case of 
speech, since it tends to detract from intelligibility. In the case of 
music the ear accepts a certain amount of this reflected sound, appar- 
ently because it tends to improve the quality of the music. It is for 
this reason that the reverberation time in music rooms is usually made 
longer than in speech room. The microphone, however, records the 
true acoustic conditions at the point of its location, and once the sound 
is recorded, the ear can during reproduction no longer ignore or dis- 
criminate against the reflected sound that was present at the micro - 




FIG. 7. Front 



of stage. 



phone position, since this reflected sound is now part of the direct 
sound from the loud speaker. 

Now, in order not to obtain excessive ratios of monaural acoustic 
perspective for the low frequencies, care must be taken to avoid long 
reverberation times for these frequencies. When the average absorp- 
tivity at a given frequency is cut in half, the reverberation time in a 
room is practically doubled. The monaural acoustic perspective for 
this case, however, becomes more than twice, and may reach values 
of three or four times, depending upon the value of the reduced 
absorptivity. This condition of increased values for the monaural 
perspective at the low frequencies is further aggravated by the fact 



Sept., 1942] MODERN Music RECORDING STUDIO 193 

that the solid-angle of reception for most microphones is larger for 
the low frequencies than for the high. 

Fig. 5 shows the reverberation characteristic of this stage, which 
has a volume of 70,000 cu-ft. The measurements were made with a 
reverberation meter of the rotating commutator type described by 
H. Olson and F. Massa in their book "Applied Acoustics." 

Fig. 6 shows a plan and elevation view of the room. The color 
scheme was prepared by the well known industrial designer, Mr. 
John Vassos, and employs a pastel shade of blue for the splays and a 
maroon for the trim (door, baseboard, chair-rail, etc.) 




FIG. 8. Rear view of stage. 

Several other studios have lately been constructed employing con- 
vex splays on the sidewalls with very good results. Among these are 
the WFAA and KGKO broadcasting studios in Dallas, Texas, the 
RCA recording studio in South America, the RCA film recording 
studios in New York, and the Walt Disney scoring stage. The only 
undesirable feature in these rooms, including this stage, is presented 
by the comparatively large expanse of the flat floor. However, the 
use of players' platforms, chairs in the room, and the judicious use of 
rugs does much to ameliorate this condition. 

The floor of this stage is of the elastically floated type. The joists 
rest on resilient steel chairs grouted in concrete. A sound-absorbent 
filler is placed between the joists, not only to dampen any resonance 



194 M. RETTINGER 

effects, but also to assist in reducing the transmission of noise from 
without. 

The monitoring room is paneled with large sheets of wood veneer 
on the sidewalls except for the wall behind the mixing console, which 
received acoustic treatment of the type employed in the state. This 
acoustic material was selected on account of its smooth absorption 
characteristic and because its low-frequency absorption was com- 
paratively high. The windows in the monitoring room are double 
panes separated by a 4-inch air-space, and the walls between the two 
sheets of glass carry sound-absorbent treatment. 

BIBLIOGRAPHY 

OLSON, H., AND MASSA, F. : "Applied Acoustics," P. Blakiston's Son & Co. 
(Philadelphia), 1934. 

MAXFIELD, J. P.: "Some of the Latest Developments in Sound Recording 
and Reproduction," Tech. Bull., Acad. Mot. Pict. Arts & Sci., Technicians Branch, 
(April 20, 1935). 

POTWIN, C. C., AND MAXFIELD, J. P.: "A Modern Concept of Acoustical De- 
sign," /. A const. Soc. Amer., 11 (July, 1939), p. 48. 

MAXFIELD, J. P., AND POTWIN, C. C.: "Planning Functionally for Good 
Acoustics," /. Acoust. Soc. Amer., 11 (April, 1940), p. 390. 

POTWIN, C. C.: "The Control of Sound in Theaters and Preview Rooms," 
J. Soc. Mot. Pict. Eng., XXXII (Aug., 1940), p. 111. 

LOOTENS, C. L., BLOOMBERG, D. J., AND RETTINGER, M. : "A Motion Picture 
Dubbing and Scoring Stage," /. Soc. Mot. Pict. Eng., (April, 1939), p. 357. 

VOLKMANN, J.: "Poly cylindrical Diffusers in Room Acoustic Design," J. 
Acoust. Soc. Amer., 13 (Jan., 1942). 



PRODUCTION OF 16-MM MOTION PICTURES FOR 
TELEVISION PROJECTION* 

R. B. FULLER AND L. S. RHODES** 



Summary. A general report on setting of procedural and dimensional practices 
for the production of 16-mm sound motion pictures for television projection. 

The paper shows that in the various steps from the original film to the final image 
on the television receiver, a considerable percentage of the frame area is lost by "crop- 
ping" in the projector, in the iconoscope, and in the kinescope. Unless this loss is 
taken into consideration and compensated for in the original planning of films for 
television, loss of image area may seriously impair the effect of the motion picture. 

The paper makes specific recommendations based upon the conclusions drawn, but 
does not attempt, in view of present conditions, to fix final aperture standards any 
further than to urge that such standards be set up by the proper group. Many of the 
factors directly concerned in production are considered with a view to the ultimate 
quality to be attained. 

Reference is made to experiences and problems met by the authors in the prepara- 
tion of animated cartoons and other films for television broadcasting. 

It is believed that both producer and motion picture technicians 
can and should review the problems connected with the preparation 
of films for television projection and telecasting and analyze the 
difficulties likely to be encountered. This might seem to be effort 
wasted at this particular time, but the new practices evolving from 
this particular field may have present and future values in contri- 
buting to the effective preparation and presentation of motion pic- 
tures for television use. 

In the preparation of motion pictures for television a number of 
facts must be taken into consideration in order to guarantee that the 
received image will fulfill the requirements of our message. In other 
words, we know what effect we want to present to the television 
audience, and so we must take into consideration and make com- 
pensations for any variations that may occur in the various steps 
between film and final image. Roughly, there are at least three 

* Presented at the meeting of the Atlantic Coast Section, Feb. 19, 1942; and 
at the 1942 Spring Convention at Hollywood, Calif.; received April 16, 1942. 
** New York, N. Y. 

195 



196 



. B. FULLER AND L. S. RHODES 



(J. S. M. P. . 



elements to be considered. First: the color loss or effect, in black- 
and-white or color: although we have a picture to start with that is 
clear in respect to its colors will we end up with the same picture? 
Second : to what extent will television faithfully reproduce the action, 
outline, or detail of the picture? Third: what loss will there be in 
the overall frame size in final projection? The last is our primary 
consideration. 




16-Mm Standard Camera Field 
16-Mm Projector Aperture 



Television Transmitter Field 
[3-5% loss on sides; 2.5% loss 
on top and bottom (linear 
dimensions)] 

Television Receiver Field 
[loss ranges from 0% to 
about 15% of transmitter 
field areal 



FIG. 1. Shaded area shows approximate reduction of image from original 
16-mm frame to the image on the television receiver. 

It is generally acknowledged by a majority of workers in the field 
of production of 16-mm films that, while general and fairly widely 
accepted standards for dimensions of such film have been set up, 
final practice policies and standard dimensions have not yet been 
widely adopted or recognized. 

In view of the state of flux and experimentation in which the 
technique of television now stands, and considering the time re- 
quired for developmental work, it is believed appropriate to note 
several special factors, paying particular attention to dimensional 
practice and procedure. 

Moreover, the coming of age of completely satisfactory direct 
sound-on-film recording in the 16-mm size has presented many 



Sept., 1942 J 16-MM PICTURES FOR TELEVISION 197 

problems new to the film-stock and equipment manufacturers and 
laboratory specialists, the general producers, and the regular users 
of finished films, whether shown on small-size home-projection screens, 
or large theater screens, or through the new transmission medium, 
television. 

At present, for 16-mm sound motion picture film, the standard 
projection aperture is 0.380 X 0.284 inch, with an allowable tolerance 
of == 0.002 inch. It is understood that the projection aperture should 
be smaller than the frame on the film for obvious reasons. 

Data on actual projection dimensions, as found in the equipment in 
various television studios, show variations in detail. One of the 
first factors to be considered is the loss of image size. We can not 
make a definite statement as to how great this loss is, because we 
find that in the several studios, and even in separate items of equip- 
ment in the same studio, there is considerable variation. Whereas 
in one instance the projector aperture used in one television studio 
was slightly smaller than standard, another studio used a slightly 
larger projection aperture, and the staff of still another studio implies 
that, although standards may have been established, a reduction of 
projection aperture dimensions may be tried if demanded by effects 
in which they are interested. 

The following is an example of the kind of problem that arises in 
processing procedure. In one case, several feet of film that had been 
optically reduced from 35 mm to 16 mm were included in 16-mm 
footage for the remainder. Due to laboratory requirements, com- 
pensation had to be made in obtaining the combined release print, 
with the result that the entire footage had proportionately wide 
spaces between frames. The laboratory had to mask the entire strip 
of film in order that the one section reduced from 35 mm would not 
show an objectionable error beyond the frame edge. This necessi- 
tated careful alignment in projection and resulted in reduced image 
sizes all around. 

Now, in discussing this problem of loss of image size we find many 
points other than those directly concerned with television projection. 
We mention them because, since we are trying to make films that 
will present ultimately a desired picture, we must consider any ele- 
ment that may change, distort, or affect the picture between, as in 
animation, the drawing of the background, and the final picture as 
viewed by the audience. 

The second point, which is relatively negligible for the most part. 



198 R. B. FULLER AND L. S. RHODES [j. s. M. P. E. 

is film shrinkage either in the original negative, in the dupe nega- 
tive, and then later, in any film that is stored over a period of time. 
Shrinkage will reduce the frame size, but the loss is figured at a 
general average of about 0.7 per cent, with an extraordinary maxi- 
mum of 2 per cent. Much of this difficulty is well realized and the 
laboratories are handling the problem rather well. 

In the printing of 16-mm film, with sprocket-holes along one edge 
and because of the edge guiding (which is not satisfactorily standard- 
ized as yet), the pull-down and the head-to-tail printing often result 
in a loss of the true frame. 

Now, let us follow an image through the steps required to bring 
the image from film to the audience and see what happens to the 
frame. Having possibly already lost some of the frame size in print- 
ing, reduction, shrinkage or ordinary handling, we are ready to pro- 
ject the strip of film into the television camera. The film is projected 
onto a photoemissive mosaic enclosed in a glass tube, and the resulting 
image is then scanned line by line. 

The photoemissive area or mosaic on which the picture is projected 
is proportioned like the film frame, roughly in a 4 to 3 ratio. Here 
we find differences of opinion and practice. Let us assume that the 
image that is projected fills the mosaic. From one studio we hear 
that this image is then "overscanned" slightly, in order to insure 
proper coverage. This means that the resulting edge must be 
masked out, and it is probable that the masking goes slightly further 
than the exact amount of overscanning in order to protect against 
any slight error of alignment. This results in a loss of about 1 /s inch 
from top to bottom, and about y 4 mc h from side to side. Another 
studio tells us that it slightly ' 'underscans, ' ' and apparently some degree 
of masking is introduced because of possible loss in definition at the 
edge. The studio did not so state. At any rate, we note that the 
image size and the frame size are being progressively reduced. 

Another television engineer said in effect that reduction of the 
original film aperture is due in some degree to the non-linearity of 
the television scanning procedure. 

Two other elements might be included here, although they can 
not be detailed at this time, partly because complete technical infor- 
mation is not available. The first is keystoning. The image pro- 
jected on the photoemissive mosaic is scanned at a 30-degree angle, 
so that the field is foreshortened and distorted. This is corrected 
before transmission by the "sawtooth voltage," but even though it 



Sept., 1942] 16-MM PICTURES FOR TELEVISION 199 

is corrected this keystoning can cause some distortion, and, hence, 
loss of frame size or proportions. 

Another of these undetermined features is difficult to explain because 
definite information could not be obtained. We have a feeling that 
there is loss of definition at the edge of the screen of the television 
receiver. If one looks at the screen from the side, the end of the 
tube has a curved surface, which apparently is cause for some dis- 
tortion. Many kinescope tubes are "blown" or molded, which 
results in a parabolic or irregular arc for the former, while the latter 
tube is a two-piece affair molded together, the surface being a true 
arc with, consequently, no distortion. 

One of the largest losses in area is entirely apart from all the fea- 
tures considered above. This is the "personal equation," which 
may enter not only at the transmission end, but also at the receiving 
end, where the observer may so tune his instrument that no more 
than 75 per cent of the image is received. The general average may 
be nearer 90 per cent in tuning accuracy, but it is still believed that 
losses do occur in this way. 

All these losses must be taken into consideration when film is 
prepared. While the various factors may occur in lesser degree 
than described above, we know that we will be wise to make all 
allowances and compensations in the very first steps. Standards 
must eventually be prescribed, and to insure faithful reproduction 
of the film, it is necessary that we put definite thought into these 
problems and arrive at standards that will save us all loss of effects 
and many headaches. Let us analize the results of the losses found 
above : 

(1) In general, the most serious result is that titles and essential 
material falling outside the middle two-thirds of the final film image 
will be in danger of being cut off. The loss of such material will be 
more serious on the sides than on the top and bottom. 

(2) In the case of technical and cartoon animation there is a defi- 
nite possibility that essential action or picture in the outer thirds 
area will be lost, although a trained animator generally attempts 
wherever possible to confine his material to the center of the field. 

(3) In live photography or studio shots, this loss may impair com- 
position or clarity. For example if the scene shows a perfectly nor- 
mal actor standing at the edge of the field, the cutting down of the 
image may result in only a part of him on the edge of the television 
screen. 



200 R. B. FULLER AND L. S. RHODES [J. S. M. P. E. 

In producing a recent animated cartoon, we had the idea that we 
could plan our scenes framed. Each picture was centered in and 
surrounded by a gray mat frame of no importance, which we would 
gladly lose before losing part of our picture. We are sad about how 
quickly this ingenious device was rejected. 

However, we suggest that field gauges be set up, to be used by 
studios producing for television films, and to be worked out by care- 
ful analysis, showing what compensations must be made for the 
probable or possible losses. 

We suggest also that finders of cameras, both for animation and 
straight shooting, have inscribed upon their view-finder lines showing 
the image to be received on the kinescope screen. As far as is known, 
there is only one make of camera that has a finder that shows only 
the projection aperture size, thus automatically showing the camera- 
man the final picture. 

To sum up, it is shown that the loss of image is more important 
than is generally realized, and it is urged that the Society make 
careful investigation of the problem. 

In our work of preparing films for television we have come upon 
a number of problems that may be of interest here. For example, 
there are many opinions on the question of the number of tones of 
grays discernible, and, of course, a great deal depends upon the sub- 
ject and the way in which it is handled. Estimates on the number 
of grays discernible in television vary from as high as 25 to as low 
as 12. It is important to note that these 12 to 25 shades are not all 
regular shades, because of the tendency of television to black out 
the darker tones of gray and burn out or wash out the lighter tones. 
So, although we can safely allow for 12 shades of gray, 8 of these 
shades could be evenly spaced in the middle range, with more subtle 
variations, while the extreme darks or lights could be much more 
widely spaced. In instances where the film is in color, it should 
be remembered, too, that two distinct colors having the same density 
may very well come out as identical tones of gray and result in a 
serious loss of definition or clarity and effect. A dark red and a 
dark blue may be transmitted as the same shade of gray, and thus 
care must be taken to consider tones rather than colors. 

We have been advised by television engineers that, in general 
average gray shades reproduce best when the gamma of the film is 
between 2.0 and 2.5 and when the maximum density range is between 
1.5 and 2.5. Apparently very superior results are achieved when the 



Sept., 1942] 16-MM PICTURES FOR TELEVISION 201 

maximum density is between 1.3 for 5 per cent transmission and 
1.8 for l ! /2 per cent transmission. 

For the most part we can say that any film that will project well 
on a theater screen will also produce equally fine results on the tele- 
vision screen, but we suggest that attention be given to this question 
of shades of color advisable in television reproduction, and here the 
motion picture may have to compromise with television procedure. 

We have developed a few little devices to help us in our work. 
We wanted, in one picture we were directing, to achieve perfect 
synchronism with a regular piece of music. We played our record 
a few times until we knew it by heart. Then we played it into the 
film recorder, and as it played, rather softly, we tapped with a pencil 
on the front of the microphone. When the sound-track was de- 
veloped we knew exactly on which frame every lesser and greater 
beat came and also how the phrases broke. Then, with a bouncing- 
ball sequence, we counted the frames; the bouncing of the ball indi- 
cated the rhythm of the music, with high bounces to give the cues for 
the narration. The result was a perfectly timed film. 

Another idea that has been favorably received in the NBC tele- 
vision studios is what we call the "tuning lead," which consists of a 
ten-second (240 frames) film exactly or almost exactly of the same 
general tone as our picture. These are used by the engineer to 
"tune" the television apparatus. On the ten-second leader are the 
words "Scene begins in ... seconds." Every twenty-four frames is a 
new number and, as the engineer watches 10-9-8-7-6-5-4-3-2-1 
there are only six frames of 1. The switch is then thrown and the 
film transferred from the monitor screen onto the actual television 
screen, perfectly tuned. 

In general, television engineering is meeting the dimensional 
practices of 16-mm motion picture production rather well; however, 
the producers may find it advisable to revise some of the practices 
derived from 35-mm procedure and establish further standardization. 



CURRENT LITERATURE OF INTEREST TO THE MOTION PICTURE 

ENGINEER 



The editors present for convenient reference a list of articles dealing with subjects 
cognate to motion picture engineering published in a number of selected journals. 
Photostatic copies may be obtained from the Library of Congress, Washington, D. C., 
or from the New York Public Library, New York, N. Y. Micro copies of articles 
in magazines that are available may be obtained from the Bibliofilm Service, Depart- 
ment of Agriculture, Washington, D. C., at prevailing rates. 

American Cinematographer 

23 (July, 1942), No. 7 

British Film Technicians and the War (pp. 294-295, 334) G. H. ELVIN 

Warners Build Improved Scene Slating Device (pp. 296- 
297, 333-334) W. STULL 

Animated Cartoon Production Today. Pt. IV. Clean- 
ups and Inbetweening (pp. 300-303, 331-332) C. FALLBERG 

Release-Print Problems in Professional 16-Mm Produc- 
tion (pp. 304, 330-331) J. A. LARSBN, JR. 

Building a Microphone-Boom for 16-Mm. Sound Home 

Movies (pp. 310-311, 328) C. N. ALDRICH 

Try Diffused Lighting for Kodachrome Close-Ups (pp. 
314, 327-328) R. RENNAHAN 

British Kinematograph Society, Journal 

5 (April, 1942), No. 2 

Speech and the Larynx (pp. 37-44) H. HARTRIDGE 

Direct Processes for Making Photographic Prints in 

Colour (pp. 45-50) C. E. K. MEES 

The Measurement of Screen Brightness (pp. 51-55) H. ETZOLD 

Electronic Engineering 

15 (June, 1942), No. 172 
Harmonic Analysis of Waves, Containing Odd and Even 

Harmonies (pp. 13-18) P. KEMP 

Television Waveforms (pp. 19-26) C. E. LOCKHART 

Institute of Radio Engineers, Proceedings 

30 (June, 1942), No. 6 
Hearing, the Determining Factor for High-Fidelity 

Transmission (pp. 266-277) H. FLETCHER 

The Effect of Fluctuation Voltages on the Linear Detec- 
tor (pp. 277-288) J. R. RAGAZZINI 
The Use of Vacuum Tubes as Variable Impedance Ele- 
ments (pp. 288-293) H. J. REICH 
202 



CURRENT LITERATURE 



203 



L. CHADBOURNE 



E. R. GEIB 



H. G. MACPHERSON 



L. CHADBOURNE 



The Relative Sensitivities of Television Pickup Tubes, 

Photographic Film, and the Human Eye (pp. 293-300) A. Ross 

International Projectionist 

17 (May, 1942), No. 5 

War Uses of Motion Pictures Discussed at SMPE Con- 
vention (pp. 7-8) 

Maintenance and Repair of Loudspeakers (pp. 9-10) 

Underwriters Code as It Affects Projection Rooms. 
Pt. II (pp. 17, 21) 

17 (June, 1942), No. 6 

The New Victory Projector Carbons (pp. 7-8) 

The Consumption of the Positive Arc Carbon (pp. 13, 
25) 

Underwriters Code as It Affects Projection Rooms. Pt. 
Ill (pp. 17-18) 

Some New Routine Precautions in the Maintenance of 
Amplifiers (pp. 19-20) 

Motion Picture Herald, Better Theaters 

147 (June 27, 1942), No. 13 

The Film Theater on the Home Front (pp. 13-15) 
How Much Can You Reduce Arc Current to Save Cop- 
per? (pp. 26-27) C. E. SHULTZ 

Photographische Industrie 

39 (April 16, 1941), No. 16 

Neuere Richtlinien des Kino-Kamerabaus (New Direc- 
tions in Motion Picture Camera Construction), (pp. 
271-272) 

39 (May 28, 1941-July 9, 1941), No. 22-28 
Das Auflosungsvermogen bei der photographischen Auf- 
nahme (Resolving Power in Photographic Emulsions). 
Pts. 1-6 (pp. 351-356, May 28; 371-373, June 4; 385- 
388, June 11; 401-403, June 18; 418-420, June 25; 
432-434, July 2; 449-452, July 9) H. ROEDER 

Deutsche und amerikanische Kinonormen in vergleich- 
ender Darstellung (Comparative Representation of 
German and American Motion Picture Standards). 
Pts. 1-3 (pp. 378-379, June 4; 395-396, June 11 ; 410- 
412, June 18) P. HATSCHEK 

39 (July 23, 1941), No. 30 
Reinton ohne oder mit Vorausreglung (High Fidelity 

Sound With or Without Pre-Setting) (pp. 491-492) P. HATSCHEK 

39 (Sept. 24, 1941), No. 39 

Die Einheiten der Beleuchtungstechnik und ihre wech- 
selseitigen Beziehungen (Relative Values for Illumina- 
tion Units) (pp. 631-632) P. HATSCHEK 



FIFTY-SECOND SEMI-ANNUAL MEETING 

OF THE 
SOCIETY OF MOTION PICTURE ENGINEERS 



HOTEL PENNSYLVANIA, NEW YORK, N. Y. 
OCTOBER 27th-29th, INCLUSIVE 

OFFICERS AND COMMITTEES IN CHARGE 

EMERY HUSE, President 

E. ALLAN WILLIFORD, Past-President 

HERBERT GRIFFIN, Executive Vice-President 

W. C. KUNZMANN, Convention Vice-President 

A. C. DOWNES, Editorial Vice-President 

ALFRED N. GOLDSMITH, Chairman, Local Arrangements Committee 

SYLVAN HARRIS, Chairman, Papers Committee 

JULIUS HABER, Chairman, Publicity Committee 

J. FRANK, JR., Chairman, Membership Committee 

H. F. HEIDEGGER, Chairman, Convention Projection Committee 

Reception and Local Arrangements 

ALFRED N. GOLDSMITH, Chairman 



R. B. AUSTRIAN 
L. A. BONN 
M. R. BOYER 
J. C. BURNETT 
F. E. CAHILL, JR. 
A. S. DICKINSON 
W. E. GREEN 
J. A. HAMMOND 
M. HOB ART 



J. FRANK, JR. 
G. FRIEDL, JR. 



L. W. DAVEE 

P. C. GOLDMARK 

R. F. MITCHELL 



C. F. HORSTMAN 
L. B. ISAAC 
E. W. KELLOGG 

J. H. KURLANDER 

P. J. LARSEN 
J. A. MAURER 
P. A. McGuiRE 
O. F. NEU 

J. A. NORLING 



WM. H. OFFENHAUSER, Ji 

W. M. PALMER 

H. RUBIN 

V. B. SEASE 

T. E. SHEA 

E. I. SPONABLE 

J. H. SPRAY 

R. O. STROCK 

H. E. WHITE 



Registration and Information 

W. C. KUNZMANN, Chairman 



E. R. GEIB 

F. HOHMEISTER 



H. K. MCLEAN 
P. K. SLEEMAN 



Hotel and Transportation 

O. F. NEU, Chairman 



W. M. PALMER 
P. D. RIES 
C. Ross 



J. A. SCHEICK 
F. C. SCHMID 

E. S. SEELEY 



204 



H. A. GILBERT 
G. GIROUX 



M. R. BOYER 
J. C. BURNETT 

P. C. GOLDMARK 

ALFRED N. GOLDSMITH 



FALL MEETING 

Publicity Committee 

JULIUS HABER, Chairman 

SYLVAN HARRIS 
C. R. KEITH 

Luncheon and Banquet 

D. E. HYNDMAN, Chairman 

J. A. HAMMOND 

O. F. NEU 

W. H. OFFENHAUSER, JR. 

M. W. PALMER 



205 



P. A. McGuiRE 
F. H. RICHARDSON 



E. I. SPONABLE 
J. H. SPRAY 
R. O. STROCK 
H. E. WHITE 



MRS. M. R. BOYER 
MRS. A. S. DICKINSON 
MRS. J. FRANK, JR. 
MRS. G. FRIEDL, JR. 
MRS. P. C. GOLDMARK 



F. CAHILL, JR. 

T. H. CARPENTER 
L. W. DAVEE 

G. E. EDWARDS 
J. K. ELDERKIN 



Ladies Reception Committee 

MRS. D. E. HYNDMAN, Hostess 



MRS. H. GRIFFIN 
MRS. J. A. HAMMOND 
MRS. P. J. LARSEN 
MRS. O. F. NEU 
MRS. W. H. OFFENHAUSER, 
JR. 



MRS. P. D. RIES 
MRS. E. I. SPONABLE 
MRS. R. O. STROCK 
MRS. H. E. WHITE 
MRS. E. A. WILLIFORD 



Projection Committee 

H. F. HEIDEGGER, Chairman 



W. W. HENNESSY 
J. J. HOPKINS 
C. F. HORSTMAN 
L. B. ISAACS 
A. L. RAVEN 



F. H. RICHARDSON 

P. D. RIES 

J. E. ROBIN 

H. RUBIN 

R. O. WALKER 



Officers and Members of New York Projectionists Local No. 306 

HOTEL RESERVATIONS AND RATES 

Hotel Rates. The Hotel Pennsylvania extends to SMPE delegates and guests 
the following special per diem rates, European plan : 

Room with bath, one person $3 . 85-$7 . 70 

Room with bath, two persons, double bed $5. 50-$8.80 

Room with bath, two persons, twin beds $6.60-$9.90 

Parlor suites: living room, bedroom, and bath $10.00, 11.00, 13.00, 

and 18.00 

Reservations. Early in September room-reservation cards will be mailed to the 
members of the Society. These cards should be returned to the hotel as promptly 
as possible to be assured of desirable accommodations. Reservations are subject 
to cancellation if it is later found impossible to attend the meeting. 

Registration. The registration headquarters will be located on the 18th floor 
of the Hotel at the entrance of the Salic Moderne, where most of the technical 



206 FALL MEETING [J. s. M. P. E. 

sessions will be held. All members and guests attending the meeting are expected 
to register and receive their badges and identification cards required for admission 
to all sessions. 

TECHNICAL SESSIONS 

Technical sessions will be held as indicated in the Tentative Program below. 
The Papers Committee is assembling an attractive program of technical papers 
and presentations, the details of which will be published in a later issue of the 
JOURNAL. 



FIFTY-SECOND SEMI-ANNUAL BANQUET AND INFORMAL GET-TOGETHER 

The usual Informal Get-Together Luncheon for members, their families, and 
guests will be held in the Roof Garden of the Hotel on Tuesday, October 27th, at 
12:30 P. M. 

The Fifty-Second Semi- Annual Banquet and dance will be held in the Georgian 
Room of the Hotel on Wednesday evening, October 28th, at 8:00 P. M. Pres- 
entation of the Progress Medal and Journal Award will be made at the banquet, 
and the officers-elect for 1943 will be introduced. The evening will conclude with 
dancing. 

LADIES' PROGRAM 

Mrs. D. E. Hyndman, Hostess, and members of her Committee promise an 
interesting program of entertainment for the ladies attending the meeting, the 
details of which will be announced later. A reception parlor will be provided for 
the Committee where all should register and receive their programs, badges, and 
identification cards. 



MISCELLANEOUS 

Motion Pictures. The identification cards issued at the time of registering will 
be honored at a number of New York de luxe motion picture theaters listed there- 
on. Many entertainment attractions are available in New York to out-of-town 
delegates and guests, information concerning which may be obtained at the Hotel 
information desk or at the registration headquarters. 

Parking. Parking accommodations will be available to those motoring to the 
meeting at the Hotel garage, at the rate of $1.25 for 24 hours, and in the open lot at 
75 cents for day parking. These rates include car pick-up and delivery at the 
door of the Hotel. 

Golf. Arrangements may be made at the registration desk for golfing at 
several country clubs in the New York area. 

Note: The dates of the 1942 Fall Meeting immediately precede those of the 
meeting of the Optical Society of America at the Hotel Pennsylvania, New 
York, N. Y., to be held on October 30th and 31st. 

The Convention is subject to cancellation if later deemed advisable in the na- 
tional interest. 



Sept., 1942] FALL MEETING 207 

TENTATIVE PROGRAM 

Tuesday, Oct. 27 

9 : 00 a.m. Hotel Roof; Registration. 

10:00 a.m. Salle Moderne; Business and Technical Session. 
12: 30 p.m. Roof Garden; SMPE Get-Together Luncheon for members, their 
families, and guests. Introduction of officers-elect for 1943 and 
addresses by prominent members of the motion picture industry 
2:00 p.m. Radio City Music Hall Studio; Technical Session. 
8:00 p.m. Museum of Modern Art Film Library; Technical Session. 

Wednesday, Oct. 28 

9 : 00 a.m. Hotel Roof; Registration. 

9:30 a.m. Salle Moderne; Technical sessions. 

12:30 p.m. Luncheon Period. 

2: 00 p.m. Salle Moderne; Technical session. 

8:00 p.m. Georgian Room; Fifty-Second Semi-Annual Banquet and Dance. 

Thursday, Oct. 29 

9:00 a.m. Hotel Roof; Registration. 
10: 00 a.m. Salle Moderne; Technical Session. 
12: 30 p.m. Luncheon Period. 
2 : 00 p.m. Salle Moderne; Technical Session. 
8:00 p.m. Salle Moderne; Technical Session and Convention adjournment. 

Note: Any changes in the location of the technical sessions and schedules of 
the meeting will be announced in later bulletins and in the final program. 

W. C. KUNZMANN, 
Convention Vice- President 



SOCIETY ANNOUNCEMENTS 



AMENDMENTS 

At the meeting of the Board of Governors, held at Hollywood, May 3, 1942, 
the amendments of the By-Laws and Constitution given below were proposed 
and approved for submittal to the membership of the Society at one of the ses- 
sions of the Hollywood Convention. 

In view of the fact that a quorum was unobtainable at any of the sessions of the 
Convention, the amendments were held over until the approaching Convention 
to be held at New York, October 27th-29th, inclusive. 

In accordance with the requirements of By-Law XII, relating to the method 
cf acting upon proposed amendments, these amendments are published in an 
issue of the JOURNAL prior to the meeting at which they are to be presented for 
vote of the Society membership. These amendments provide for increasing 
the number of members of the Board of Governors, and are as follows: 

Proposed Amendment of Article V 

The Board of Governors shall consist of the President, the Past-President, 
the five Vice-Presidents, the Secretary, the Treasurer, the Section Charimen, and 
ten elected Governors. Five of these Governors shall be resident in the area 
operating under Pacific and Mountain Time, and five of the Governors shall be 
resident in the area operating under Central and Eastern Time. Two of the 
Governors from the western area, and three of the Governors trom the eastern 
area shall be elected in the odd-numbered years, and three of the Governors from 
the western area and two of the Governors from the eastern area shall be elected 
in the even-numbered years. The term of office of all elected Governors shall 
be two years. 

Proposed Amendment of By-Law I/I, Sec. 2 

Nine members of the Board of Governors shall constitute a quorum at all 
meetings. 

Proposed Amendment of By-Law III, Sec. 1 

The Board of Governors shall transact the business of the Society between 
members' meetings, and shall meet at the call of the President, with the proviso 
that no meeting shall be called without at least seven (7) days' prior notice, 
stating the purpose of the meeting, to all members of the Board, by letter or by 
telegram. 

208 



SOCIETY ANNOUNCEMENT 



209 



ADMISSIONS COMMITTEE 

At a recent meeting of the Admissions Committee, the following applicants 
for membership were admitted into the Society in the Associate grade: 



CORCORAN, J. P. 
2213 Midvale Ave., 

West Los Angeles, Calif. 
DONNELLEY, THORNE 

Photographic Science Laboratory, 

Anacostia, D. C. 
GOLDBERG, H. E. 

Eastman Kodak Company, 

Rochester, N. Y. 
HANSON, GEORGE 
2960 Ettrick St., 

Los Angeles, Calif. 
JOHNSTON, E. R. 

742 Lakeview Blvd., 

Seattle, Wash. 
KRAUSS, E. D. 
1021 Chavez St., 
Burbank, Calif. 



LEGRAND, C. C. 

Mole-Richardson Co. 
941 N. Sycamore Ave., 

Hollywood, Calif. 
LOBALBO, C. F. 
3202 Ampere Ave., 

Bronx, N. Y. 
NAVE, F. A. 
Rt. 2, Box 263, 

Oakdale, Calif. 
REEDY, W. A. 

Weston Electrical Instrument Corp. 

Newark, N. J. 
SHERMAN, L. F., JR. 
Calton Court, 

New Rochelle, N. Y. 
WILSON, W. G. 
2411 East 15th St., 
Kansas City, Mo. 



WOODWARD, H. L., JR. 
Signal Photo Laboratories, 
Army War College, 
Washington. D. C. 



In addition, the following applicants have been admitted to the Active grade: 



BERTRAM, E. A. 

DeLuxe Laboratories 
441 West 55th St., 
New York, N. Y. 
BARNET, STAN 

333 West 57th St., 
New York, N. Y. 



DEVRY, E. B. 

1111 Armitage Ave. 

Chicago, 111. 
OSBORN, L. G. 

Western Electric Co., Ltd., 
152, Coles Green Road, 
London. N. W. 2, England 



MEMBERS OF THE SOCIETY 

LOST IN THE SERVICE OF 

THEIR COUNTRY 



FRANKLIN C. GILBERT 



JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

VOLUME XXXIX OCTOBER, 1942 



CONTENTS 

PAGE 

The Technique of Production Sound Recording 

H. G. TASKER 213 

Prescoring and Scoring B. B. Brown 228 



A Study of Flicker in 16-Mm Picture Projection 

E. E. MASTERSON AND E. W. KELLOGG 232 



Developments in Time-Saving Process Projection 

Equipment R. W. HENDERSON 245 

Current Literature 258 

Fifty-Second Semi-Annual Meeting, Hotel Pennsyl- 
vania, New York, N. Y., October 27th-29th, Incl. 
General Information 259 

Abstracts of Papers 263 

(The Society is not responsible for statements of authors.) 



JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

SYLVAN HARRIS, EDITOR 

Board of Editors 

ARTHUR C. DOWNES, Chairman 

JOHN I. CRABTREE ALFRED N. GOLDSMITH EDWARD W. KELLOGG 

CLYDE R. KEITH ALAN M. GUNDELFINGER CARLETON R. SAWYER 

ARTHUR C. HARDY 

Officers of the Society 

*President: EMERY HUSE, 

6706 Santa Monica Blvd., Hollywood, Calif. 
* Past-President: E. ALLAN WILLIFORD, 

30 E. 42nd St., New York, N. Y. 
*Executive Vice-President: HERBERT GRIFFIN, 

90 Gold St., New York, N. Y. 
** Engineering Vice-President: DONALD E. HYNDMAN, 

350 Madison Ave., New York, N. Y. 
* Editorial Vice-President: ARTHUR C. DOWNES, 

Box 6087, Cleveland, Ohio. 
** Financial Vice-President: ARTHUR S. DICKINSON, 

28 W. 44th St. , New York, N. Y. 
* 'Convention Vice-President: WILLIAM C. KUNZMANN, 

Box 6087, Cleveland, Ohio. 
4 'Secretary: PAUL J. LARSEN, 

1401 Sheridan St., N. W., Washington, D. C. 
* Treasurer: GEORGE FRIEDL, JR., 

90 Gold St., New York, N. Y. 

Governors 

*MAX C. BATSEL, 501 N. LaSalle St., Indianapolis, Ind. 
**FRANK E. CARLSON, Nela Park, Cleveland, Ohio. 

*JOHN G. FRAYNE, 6601 Romaine St., Hollywood, Calif. 

*ALFRED N. GOLDSMITH, 580 Fifth Ave., New York, N. Y. 
**EDWARD M. HONAN, 6601 Romaine St., Hollywood, Calif. 

*I. JACOBSEN, 177 N. State St., Chicago, 111. 
**JOHN A. MAURER, 117 E. 24th St., New York, N. Y. 

*LOREN L. RYDER, 5451 Marathon St., Hollywood, Calif. 

* Term expires December 31, 1942. 
** Term expires December 31, 1943. 



Subscription to non-members, $8.00 per annum; to members, $5.00 per annum, included 
in their annual membership dues; single copies, $1.00. A discount on subscription or single 
copies of 15 per cent is allowed to accredited agencies. Order from the Society of Motion 
Picture Engineers, Inc., 20th and Northampton Sts., Easton, Pa., or Hotel Pennsylvania, New 
York, N. Y. 

Published monthly at Easton, Pa., by the Society of Motion Picture Engineers. 

Publication Office, 20th & Northampton Sts., Easton, Pa. 

General and Editorial Office, Hotel Pennsylvania, New York, N. Y. 

Entered as second-class matter January 15, 1930, at the Post Office at Easton, 

Pa., under the Act of March 3, 1879. Copyrighted, 1942, by the Society of Motion 

Picture Engineers, Inc. 



THE TECHNIQUE OF PRODUCTION SOUND RECORDING 

HOMER G. TASKER** 



Summary. Although sound recording differs greatly from motion picture 
photography, it involves many analogous techniques and some similar processes. 
Sound recording requires special apparatus to transform sound into energy capable 
of exposing motion picture film. Its reproduction from the film requires additional 
transformations involving other specialized apparatus. 

Good sound pick-up on the motion picture set involves acoustic conditioning quite 
analogous to set lighting, camera angle selection, etc. The sound crew is provided with 
flexible means for microphone placement and with controls and monitoring devices 
for observation of the results obtained. The film recording machine is a specialized 
mechanism requiring precision comparable to that of the motion picture camera. 
Its operation entails skillful adjustments. The sound department cooperates with the 
laboratory department in the establishment and interpretation of processing controls. 

In discussing the aural or sound problems in the production of 
motion pictures, three introductory tasks must be undertaken : 

(1) To distinguish the problems of recording the aural elements of a motion 
picture scene from those of recording the visual elements. 

(2} To indicate the scope of production sound recording, as distinguished 
from scoring and pre-scoring, and from re-recording or sound blending. 

(5) To introduce, in elementary form, the recording and reproducing appa- 
ratus common to all three of these recording activities. 

(1) As entertainment media, the visual and aural elements of a 
motion picture scene supplement each other in that sound contributes 
many details of thought, action, or emotion not possible to the pic- 
torial side and vice versa. As media to be recorded upon the motion 
picture film, they differ in the extreme. The visual element, properly 
illuminated, is capable of exposing the film directly through the 
agency of the camera lens, but sound is quite as invisible to the 
camera eye as it is to the human eye. Hence, it requires very con- 
siderable transformations or translations before it can be photo- 
graphed on the film, and again before it can be reproduced in the 
theater in a form to be interpreted by the human ear. 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received Aug. 
20, 1942. 

** Paramount Pictures, Inc., Hollywood, Calif. 

213 



214 H. G. TASKER U. s. M. p. E. 

Further, the camera and the microphone differ, as do the eye and 
the ear, in that off-stage objects are almost entirely ignored by the 
camera, while off-stage sounds are almost as well recorded as the 
wanted sounds from the scene itself. The limitations thus imposed 
may be quite severe. 

Although the visual and the aural elements both involve time as 
the very essence of the entertainment values to be recorded, the 
characteristics of the eye fortunately permit the simulation of con- 
tinuous motion through the rapid succession of a large number of 
still pictures, whereas sound requires absolute continuity of the re- 
cording and of the subsequent reproduction. Fortunately, both these 
requirements can be met with motion picture film. 

Nevertheless, there are many motion picture processes common to 
sight and sound, for the record of sound is photographic in character, 
and there is basic similarity between the laboratory processes involved 
in producing and multiplying these records and those employed for 
the picture. Moreover, as they leave the studio for projection in 
theaters throughout the world, they occupy, side by side, the same 
piece of film. 

(2) Production sound recording may be defined as the recording 
of sound that takes place simultaneously with the photographing of 
the scene. Ordinarily, this includes dialog and such incidental foot- 
steps, door slams, and other noises as originate within the camera 
angle. 

Scoring is the subsequent recording of music to accompany the 
scene. Pre-scoring is the prior recording of instrumental or vocal 
music to be played back during the photographing of a scene to estab- 
lish musical tempo to which the actors may synchronize their move- 
ments. 

Re-recording is the final blending together of the dialog, the pre- 
or post-scored music, the "character" sound-effects such as crowd 
murmurs and factory noises, and the effects separately recorded to 
accompany scenes photographed without sound, etc. 

(3) A great deal has been written about the design and character- 
istics of sound recording and reproducing equipment but not so much 
about the nature of the work to be accomplished with these tools or 
about the techniques involved. The emphasis here will be on the 
latter rather than on the former features. Details of the equipment 
may be found in the appended bibliography. 

For this reason the basic sound-recording and reproducing system 



Oct., 1942] 



PRODUCTION SOUND RECORDING 



215 



will be introduced here in quite elementary form. Subsequent 
references will be made to specific characteristics of certain apparatus 
as they bear on matters of technique. 

Referring to Fig. 1 and beginning at the lower left of the diagram, 
the essential elements of a sound-recording system are : 

(a) Microphone (First Transformation). Transforms sound 
energy into electrical energy. Several different types 1 - 2 are used de- 
pending upon the requirements, but each is a high-quality device 
responsive to the air pressure changes or air particle movements 



MOTION PICTURE STUDIO 

Q 

MODULATOR OPTICS 



LIGHT SOURCE 

SOUND NEGATIVE x 
FILM 



o 




AMPLIFIER 
VOLUME CONTROL 

MICROPHONE 



THEATER 



Q 



OPTICS 



LIGHT 
SOURCE 
POSITIVE 
FILM 



* 



PHOTOCELL 



VOLUME CONTROL 
AMPLIFIER 



L / 



LOUD SPEAKER 



FIG. 1. Elements of sound-recording and reproducing systems. 

which characterize sound so that the result is an electrical copy of 
whatever sound impinges upon the microphone. 

(b) Amplifier. Increases the above-mentioned electrical energy 
to usable proportions. The output of the microphone is very feeble. 
One milli-microwatt is typical, although this will vary with the type 
of microphone and other circumstances from Viooo to nearly 1000 
times that value. About one watt is needed for recording. Hence 
the amplification must be very great and must also be of the highest 
quality and controllable with precision. 

(c) Electrooptical Modulator (Second Transformation). Exposes 
the sound negative motion picture film under control of the above- 



216 H. G. TASKER [J. a M. P. E. 

described amplified electrical energy. The motion picture industry 
is about equally divided in the use of two types of modulators, both 
of which employ a steady source of light plus electromagnetic means 
for controlling the amount of this light that reaches the film. In the 
"light- valve" type of modulator 3 pairs of metallic ribbons surrounded 
by a strong magnetic field alternately separate and converge to 
control the passage of light in response to the amplified current from 
the microphone. The system is usually so aligned as to expose the 
sound-track uniformly across its full width but in varying degree 
along its length, so as to produce the "variable-density" type of 
sound-track. In the "galvanometer" type of modulator 4 the same 
purpose is served by the rotary oscillation of a small mirror mounted 
on an electromagnetic structure in such a way as to be responsive 
to electrical energy. The system is usually so arranged as to ex- 
pose a fraction only of the width of the sound-track, the magnitude 
of this fraction varying lengthwise of the film so as to produce the 
"variable-area" type of sound-track. 

(d) Film-Driving Mechanism. Moves the film past the exposure 
point with a very high degree of uniformity of speed. 5 - 6 It has proved 
useful to separate the sound recorder from the picture camera. The 
necessary synchronism is maintained by one of several types of motor 
systems including a-c interlock, 7 d-c interlock, 8 and synchronous. 

(e) Auxiliary Apparatus. This includes such necessary elements 
as volume controls, fixed or variable equalizers, volume indicators, 
monitoring equipment, power supplies, etc. 

Subsequently to the necessary processing of the sound negative and 
the making of positive prints the equipment necessary to reproduce 
sound from this film in synchronism with the picture, whether for 
studio purposes or for projection in theaters, is as follows : 

(/) Film-Driving Mechanism. Moves the sound-track past the 
reproducing point with the required uniformity of speed and in 
synchronism with the picture. In most studio processes the sound- 
track and the picture are on separate films and the sound-reproducing 
mechanism is driven by a-c interlock motors or by a "dual film 
attachment" 9 to the picture mechanism, as the requirements dictate. 
When released in theaters a "composite print" is used in which 
sound and picture are printed on adjacent areas of the same film. 
In this case, the sound and picture mechanisms are combined, and 
synchronism is afforded by locating a given picture frame twenty 



Oct., 1942] PRODUCTION SOUND RECORDING 217 

frames behind the corresponding sound modulation so that they will 
appear in their respective "gates" of the mechanism simultaneously. 

(g) Optics and Photocell (Third Transformation).* Produces 
electrical energy corresponding to the varying optical transmission of 
the film record. A steady source of light is provided together with an 
optical system so arranged that light passing through a narrow slit 
(transversely of the sound-track) reaches the photoelectric cell. As 
the sound-track moves through the mechanism, the variation in the 
density or in width of the sound-track causes the required fluctuations 
in the light falling upon the photoelectric cell. 

(h) Amplifier. Increases the electrical energy to useful propor- 
tions. The photoelectric-cell output is very feeble under some condi- 
tions. In good theater practice the amount of sound-modulated 
electrical energy required to drive the loud speakers varies from 15 to 
100 watts, depending upon the size of the theater, etc. Hence theater 
amplifying systems must have not only considerable gain but also 
quite high output levels with low distortions. 

(i) Loud Speakers (Fourth Transformation). In response to the 
amplified electrical energy, the loud speakers reproduce in the theater 
sound corresponding to that which originally appeared at the micro- 
phone. Simple radio types of loud speakers, even though large in 
scale, will not serve the requirements adequately. For good results, 
special high-frequency speakers equipped with multicellular horns 
are required to minimize high-frequency distortion and to afford uni- 
form distribution of intelligibility throughout the theater. In order 
to exercise proper judgment in scoring, re-recording, and reviewing 
operations, similar equipment must be used in the studio. 

THE TECHNIQUE OF SOUND PICK-UP 

(4) To point a camera at an indoor object, turn on a light, and 
snap the shutter is one thing. To produce photography having con- 
sistent beauty and story-telling power is quite another. It is so with 
sound. There must be acoustic "lighting" or "conditioning" to ob- 
tain the best results. Microphone "placement," like camera 
"angle," must be carefully worked out. 



* The transformations referred to are those mentioned at the beginning as 
being unique to sound recording and sound reproduction, as distinct from picture 
photography; hence the film -processing transformations are not numbered among 
them. 



218 H. G. TASKER [j. s. M. p. E. 

Consider first the problem of intelligibility vs. angle, as the actor is 
photographed from various angles in a given scene. The voice is 
directional in its frequency characteristic. Forward from the face it 
is much more brilliant acoustically and carries more intelligibility 
than toward the rear. Hence if two actors face each other and the 
camera shoots over the shoulder of one into the face of the other, and 
if the microphone takes the same view of the situation as the camera, 
then the face-on voice will be good but the other will have a muffled 
yet rather roomy or reverberant quality. Unfortunately, the micro- 
phone exaggerates the effect over that observed by human ears in the 
same location. But even in the absence of such exaggeration, the 
effect would still be unwanted. A digression is in order to point out 
why. 

It is not the purpose of alternate angle shots over one shoulder of 
one actor into the face of a second actor, and vice versa, to give an 
audience the sensation of having been swung back and forth through 
space to have a look first at one actor and then the other, nor yet 
that the terra firma that supports the actors is performing similar 
gyrations. On the contrary, if such a scene is well done in all tech- 
nical respects, the audience should experience no such gyratory effect, 
but only a snapping of attention from one actor to the other at the 
instants of greatest interest or of greatest pertinence to the story. 
The same considerations govern sound recording for such a scene, and 
accordingly the microphone, though necessarily above the camera 
angle, should always be in front of and facing the person speaking. 
This requires extreme mobility of the microphone mobility available 
on the instant and accomplished without making noise, without 
appearing in or casting a shadow on the scene. This demand has led 
to the development of very excellent microphone booms which af- 
ford great freedom of microphone movement and direction, con- 
trollable from positions outside the camera angle. By their use the 
microphone is manipulated into correct position from instant to 
instant by the "boom" operator under the occasional guidance of the 
chief sound man or "production sound mixer," who is also controlling 
other portions of the system and observing the sound quality pro- 
duced as discussed later. 

The type of scene just described consumes a lot of Hollywood film 
footage each year, but there are, of course, other cases in which the 
audience should experience special orientation with respect to the 
scene or should be made aware of such acoustic qualities of the scene 



Oct., 1942] PRODUCTION SOUND RECORDING 219 

as the reverberation of a cathedral, the hollowness of a cave, etc. In 
other words, the character of the sound sought for by the mixer is 
always governed by "good theater." 

Such effects are rather easier to obtain when wanted than avoided 
in scenes where they are inappropriate. The microphone is a "one- 
eared" device, and tends to exaggerate the reflections from walls and 
other surfaces that give rise to room effects so that the mixer's con- 
stant struggle is to reduce them. 

The case of strong short-path reflections encountered during close- 
ups such as at lunch-counters or in other confined spaces is so typical 
of the mixer's acoustic problems that a close look at this case will illus- 
trate the tools and techniques employed by the mixer for nearly all 
other cases as well. 




. MICROPHONE 



WAVES ARRIVING OUT OF PHASE 



REFLECTING SURFACE 

h DIRECT PATH { 



\* REFLECTED P*TM j 

FIG. 2. Interference due to short-path reflections. 

The objectionable character of these short-path reflections lies in 
the fact that they may arrive at the microphone with such strength, 
due to their shortness of path, that they may nearly cancel the direct 
sound at certain frequencies or objectionably overemphasize it at 
other frequencies. As illustrated in Fig. 2, this is determined by the 
relation of wavelength to difference of path between the direct and 
the reflected portions. 

Such reflections may be reduced during rehearsals by carefully 
probing the available microphone space to find the spot least affected 
by the reflections without suffering too much loss of voice brilliance 
due to unfavorable angle as discussed earlier. The properties of 
certain recently developed directional microphones 1 - 1 may also be em- 
ployed to discriminate somewhat in favor of the direct as against the 



220 H. G. TASKER [j. S. M. P. E. 

reflected sounds but with rather less benefit than might be expected. 
Fig. 3 illustrates a microphone whose directional properties (see Fig. 
4) are adjustable to embrace practically every directional character- 
istic now attainable. A pressure-responsive unit which is essentially 
non-directional (see Fig. 4D) is mounted in close association with a 
velocity-responsive element whose polar directional diagram is a pair 
of circles (see Fig. 4K) indicating full response in one axis and zero 
response at right angles thereto. As may be seen in the intermediate 
diagrams, these elements may be combined in varying degrees to 




FIG. 3. Unidirectional microphone. 

give a variety of response patterns of the general type known as 
"cardioid." 

If now the mixer attempts to use any one of these patterns to dis- 
criminate between two sounds differing in angle by as little as thirty- 
five degrees, as in the example of Fig. 2, then he must choose between 
having the direct sound arrive at an angle of nearly maximum sensi- 
tivity and let the reflected sound be scarcely attenuated, or let the 
reflected sound arrive at an angle of nearly zero pick-up, which will 
give excellent discrimination but will always find the direct sound 
arriving at a point of much less than maximum sensitivity. In the 
latter case, the major pick-up axis may enhance set noises or smaller 
reflections from other surfaces to such an extent that these become 
limiting factors. 



Oct., 1942] 



PRODUCTION SOUND RECORDING 



221 



The advantages of such microphones are not gained without some 
penalty. Nearly all microphones are sufficiently bulky and heavy to 
impair their mobility when swung at a radius of ten to eighteen feet 
on the modern microphone boom. These "unidirectional" or multi- 
duty microphones, consisting as they do of a pressure and a velocity 
microphone combined in one case, always have greater weight and 
bulk than other microphones of comparable sensitivity. 



COMBINATION 



DYNAMIC (D) IN V. 
BIBBON (R)IN% 

INDEX I 

INDEX J 




FIG. 4. Formation of directivity patterns by combinations of ribbon 

and dynamic microphone elements. 

/ Directivity \ T _ efficiency for sound of random incidence 
\ Index / efficiency for sound of normal incidence 

average efficiency for all angles of sound 
incidence in rear hemisphere 



J 



average efficiency for all angles of sound 
incidence in front hemisphere 



It happens that the strong short-path reflections are most ..1>\ iotis 
to the ear at frequencies below 1000 cycles. If the mixer has done his 
best, with the cooperation of the boom operator, to locate a fuvorabK 
position and orientation for the microphone and still finds himself 
having reflection troubles, he may be able to effect an improvement 
by adjusting his low-frequency equalizer or suppressor. If not, lu 
may be able to find a spot favorable to reducing the low-f reqiu i u \ 
reflections at the cost of some brilliance, but he may be able to restore 
some of the latter with his high-frequency equalizer. Sometime v 
though seldom in this type of problem, he can introduce acoustic 
absorbing material that will help. 10 



222 H. G. TASKER [J. s. M. P. E. 

After fighting one of these ' 'lunch-counter" reflections for half a day 
while the boy and girl finish their coffee and doughnuts, quarrel, kiss 
and make up, and exhaust the sound crew's patience, the crew usually 
go home resolved that if they ever become writers or producers or 
executives, there will be no more lunch counter scenes! 

The chances are that next day they may work in a well furnished 
living-room set that gives no trouble at all; or in a bare tenement 
bedroom having plenty of "cistern" effect but in which by laying a 
rug on the floor (out of the camera angle) or by hanging a blanket or 
two in some area that will not interfere with the lighting, the mixer 
can get the "feel" of the set about right in his monitor. In general 
the considerations of time-lag and intensity of reflection in the larger 
spaces make proper sound pick-up a simpler problem. Of course, 
when a large "exterior" set must be constructed inside a stage, the 
stage-wall reflections must be held abnormally low if naturalness is to 
be achieved. Most sound stages are treated on the inside with two 
inches of rock wool furred out two or more inches from the solid con- 
struction, with the result that the reflections 11 are not objectionable 
except in the case of exterior scenes. In such cases the sound man is 
in contact with the job days in advance, learning the camera angles 
to be used, studying the acoustic problems to be met, planning the 
treatments necessary, etc. Nor does the sound department neglect to 
develop the cooperation of the art department in shaping structures or 
choosing material that will minimize the sound-reflection problem. 10 

We have seen then that the mixer's "acoustic lighting" problem is 
primarily one of avoiding excessive reflections of three distinct types : 

(a) Confined space or "barrel" reflections. 
(6) Medium space or "roominess" reflections. 
(c) Large space or "reverberant" reflections. 

To any one of these reflection problems he may apply one or all of 
the following controls : 

(a) Proper choice of materials or designs, through cooperation with the art 

department. 
(&) Microphone placement. 

(c) Microphone directional properties. 

(d) Blanketing to absorb reflections. 

Noises occurring within the motion picture set are objectionable 
except in rare instances when they are in keeping with the character 
of the action. This is particularly true of such modern noises as 



Oct., 1942] PRODUCTION SOUND RECORDING 

traffic and machinery sounds when the scene being photographed be- 
longs to an earlier period in history. To reduce the penetration of 
traffic and other external noises, stage walls are heavily insulated, 11 
some having attenuations as high as 70 db. Mechanical noises arising 
within the stage from cameras, wind machines, etc., are reduced by 
careful design, by elimination of gears, and by the provision of good 
insulating housings where necessary. 12 ' 13 - 14 The relative effect of the 
noises that remain, as compared to the wanted sounds arising from the 
action, may be further reduced by taking advantage of the direc- 
tional properties of microphones. Refer again to Fig. 4 for the 
effectiveness of such microphones in reducing noises of random inci- 
dence as compared to direct sounds. 

ADDITIONAL QUALITY CONTROL MEASURES 

(5) While acoustic considerations and microphone character- 
istics are of utmost importance to successful sound recording for 
theater projection, there must also be adequate control of volume. 
In this respect also it is "good theater" that governs. In actual life a 
dance band will produce more than ten million times the sound 
energy of a quiet scene in a murder mystery. This is a 70-db dif- 
ference, but if the murder scene were recorded 70 db lower in level 
than a properly chosen dance band level, the dialog would be com- 
pletely inaudible in the theater. We must, instead, enable the 
persons in the back row of the theater to hear the quiet scene dis- 
tinctly, even though softly, and for this purpose the original 70-db 
difference in level must be reduced to about 25 db. Hence the mixer 
must be constantly alert to make the proper volume adjustments of 
the material he is recording. To this end he is provided with a "unit 
volume control" for each microphone (normally one to as many as 
four) plus an inclusive or master volume control. To help him gauge 
the correct level, he is provided with a volume-indicator meter whose 
deflections are an indication of the modulation reaching the film. 
He is provided also with an audible monitoring system, usually a 
headset of high quality, 15 which enables him to listen critically to the 
overall result of his work and to apply the judgment that his task 
demands. 

It is true that in the re-recording process some opportunity is 
afforded for the refinement of the production mixer's work. However, 
the signal-to-noise ratio of the film (of the order of 55 db) becomes a 
limiting factor. If the production mixer records a "quiet" original 



224 H. G. TASKER [J. s. M. p. E. 

scene about 15 db lower than he should, then in attempting to correct 
this error during re-recording, a very objectionable amount of film- 
surface noise would be introduced. If, on the other hand, a dance 
band were recorded 10 db too loud, the result would be severe dis- 
tortions in the recording which could never be corrected. Hence, it 
is necessary that the production mixer come as nearly as possible to 
the correct level in the original recording. 

Experience has indicated that there must also be considerable ad- 
justment of frequency characteristic 16 to secure proper theater pres- 
entation. In some studios this step is reserved solely for the re- 
recording process. In others, the production mixer makes a first- 
order correction, leaving refinement to the re-recording mixer. 

Having used the foregoing tools and methods in the control of 
sound and quality to the best of his ability, the production sound 
mixer must exercise the further control of suggestion and rejection. 
The most successful mixers develop a high degree of tact and good 
judgment, knowing just when a word of suggestion to the actor or 
director will secure a more effective sound recording, and just when 
sound imperfections are of such importance that he must request 
additional takes which may cost anywhere from fifty to several 
hundred dollars. 

TECHNIQUE OF FILM RECORDING 

(6) In the editing of a motion picture, great advantage is had if 
the sound record is on a strip of film separate from the picture. It is 
of further advantage if the sound-recording machine is separate from 
the picture camera a practice followed without exception in Holly- 
wood. These two mechanisms must run in synchronism. In "proc- 
ess" photography shots, a predetermined phase relationship between 
the camera and the process projector is also involved, and for such 
shots all studios use some form of a-c interlocking motor system. 7 
Several studios use this system for all studio operations and in some 
cases even for location shooting. Other studios substitute salient-pole 
synchronous motors for all production shooting except process 
photography scenes. Neither of these systems is very economical of 
electrical power and in location work, power-supply takes on consider- 
able importance. For this reason, most studios employ some form 
of d-c interlock for location work and especially for super-portables. 8 

The sound-film recorder, like the motion picture camera, is a 
highly specialized and very precise piece of mechanism. The design 



Oct., 1942] PRODUCTION SOUND RECORDING 225 

requirements to secure the necessary uniformity of film motion are 
adequately discussed in the literature; 6 - 8 so also are the requirements 
and characteristics of the modulators by means of which exposure of 
the film is produced corresponding to the sound impinging upon the 
microphone. 3 - 4 One such system is introduced schematically into 
Fig. 5 to afford some idea of the operational problems involved. 

In this illustration, the pole-pieces of the electromagnetic yoke are 
cut away and the light-valve ribbons are much enlarged so that their 
position and action may be clearly seen. Light from the lamp on the 




'CONDENSER LENS 



FIG. 5. Light-valve modulator system. 

left is spread quite uniformly over the slit between the light-valve 
ribbons by setting the condenser lens in a slightly out-of -focus posi- 
tion. When a current passes through the ribbons from a to b, the 
ribbons will separate allowing more light to pass between them, and 
vice versa. The objective lens focuses this light into a thin, sharp line 
on the motion picture film. If the film were at rest, the intensity of 
this line would remain constant, but its thickness would vary exact 1\ 
in accordance with the spacing of the light- valve ribbons; but since 
the film is moving at a uniform speed of 90 feet per minute, the effect 
is to vary the exposure lengthwise of the film and hence produce 
variable-density sound-track. The drum that carries the film is 
mechanically filtered from the rest of the driving mechanism. Great 



226 H. G. TASKER [J. s. M. p. E. 

care is taken in the design of the mechanical filter, and in some types 
the variation of speed or "flutter" is held to less than 0.05 per cent of 
the designated uniform speed. 

The light- valve ribbons weigh only two millionths of an ounce each, 
are about six mils wide and half a mil thick, and must be spaced about 
a mil apart and accurately parallel. The stringing and adjusting is 
ordinarily done by a specialist, who also takes care of certain other 
equipment requiring precise adjustment. In some studios, however, 
each recordist (recording machine operator) strings and adjusts his 
own light-valves as required. 

During operation, these ribbons are "biased" electrically to a 
spacing of about Vio of a mil to effect reduction of film grain-noise by 
reducing the light reaching the negative. This results in darker ex- 
posure of the positive, and hence less reproduced noise during intervals 
of silence or of low sound level at the microphone. 17 ' 18f 19 To make 
the biasing adjustment properly, the recordist must carefully deter- 
mine the sensitivity of the valve and then adjust the biasing current 
to the proper amount. The accuracy required is approximately ten 
millionths of an inch. 

In the galvanometer type of modulator, comparable considerations 
apply, except that in "type B" variable-area recording, as practiced 
at one studio, no noise-reduction amplifiers are involved. 

There are many other adjustments of the recording machine and 
associated equipment that the recordist must make. In addition, he 
usually starts and stops the entire system on signal from the stage and 
applies "end strip" exposures for processing control, etc. 

The sound department must participate actively in the establish- 
ment of processing control limits and in the interpretation of the daily 
results, and must provide the laboratory with most of the specially 
exposed "strips" that are required. Sound quality controls for 
processing of variable-density recordings always include sensitometer 
strips for control of processing gamma. In the case of fine-grain 
films, which afford considerable improvement in grain-noise and 
distortion, 20 it is also necessary to make occasional light- valve 
gamma strips because of the failure of the photographic reciprocity 
law and the fact that this failure is not uniform with conditions. 
Most studios also use the newly developed technique of inter-modula- 
tion measurement. This method affords a useful means of establish- 
ing correct print density for given negative processing conditions. 



Oct., 1942] PRODUCTION SOUND RECORDING 227 

REFERENCES 

(All references are to J. Soc. Mot. Pict. Eng.) 

1 HOPPER> F - L ' : "Characteristics of Modern Microphones for Sound Record- 
ing," XXXIII (Sept., 1939), p. 278. 

1 LIVADARY, J. P., AND RETTINGER, M.: "Uni-Directional Microphone Tech- 
nic," XXXII (Apr., 1939), p. 381. 

8 FRAYNE, J. G., AND SILENT, H. C.: "Push-Pull Recording with the Light 
Valve," XXXI (July, 1938), p. 46. 

4 DIMMICK, G. L.: "The RCA Recording System and Its Adaptation to Vari- 
ous Types of Sound-Track," XXXIX (Sept., 1942), p. 258. 

6 KELLOGG, E. W.: "A Review of the Quest for Constant Speed," XXVHI 
(Apr., 1937), p. 337. 

ALBERSHEIM, W. J., AND MACKENZIE, D.: "Analysis of Sound-Film Drives," 
XXXVII (Nov., 1941), p. 452. 

7 TASKER, H. G.: "Improved Motor System for Self-Phasing of Process Pro- 
jection Equipment," XXXVII (Aug., 1941), p. 187. 

8 HOLCOMB, A. L.: "Multi-Duty Motor System," XXXTV (Jan., 1940), p. 103. 

9 BORBERG, W., AND PINNER, E.: "The Simplex Double Film Attachment," 
XXXIV (Feb., 1940), p. 219. 

10 THAYER, W. L. : "Solving Acoustic and Noise Problems Encountered in Re- 
cording for Motion Pictures," XXXVH (Nov., 1941), p. 525. 

11 LOYE, D. P.: "Acoustic Design Features of Studio, Stage, Monitor Rooms, 
and Review Rooms," XXXVI (June, 1941), p. 593. 

11 ROBBINS, J. E.: "Silent Variable-Speed Treadmill," XXXIV (June, 1940), p. 
632. 

13 ALBIN, F. G.: "Silent Wind Machine," XXXII (Apr., 1939), p. 430. 

14 CLARKE, D. B., AND LAUBE, G.: "Twentieth Century Camera," XXVI 
(Jan., 1941), p. 50. 

u ANDERSON, J. L.: "High Fidelity Head Phones," XXXVH (Sept.. 1941), p. 
319. 

16 MORGAN, K. F., AND LOYE, D. P.: "Sound Picture Recording and Repro- 
ducing Characteristics," XXXJI (June, 1939), p. 643. 

17 SANDVIK, O., AND GRIMWOOD, W. K.: "An Investigation of the Influence of 
Positive and Negative Materials on Ground Noise," XXV (Aug., 1940), p. 126. 

M KELLOGG, E. W.: "Ground Noise Reduction Systems," XXXVI (Feb., 1941), 
p. 137. 

19 SCOVILLE, R. R., AND BELL, W. L.: "Design and Use of Noise Reduction 
Bias Systems," XXXVIII (Feb., 1942), p. 125. 

20 DAILY, C. R., AND CHAMBERS, I. M.: "Production and Release Applications 
of Fine-Grain Films for Variable- Density Sound Recording," XXXVm (Jan.. 
1942), p. 45. 

HOLCOMB, A. L. : "Motor Drive Systems for Motion Picture Production;" 
presented at the 1942 Spring Meeting at Hollywood, Calif.; to be published in a 
forthcoming issue of the JOURNAL. 



PRESCORING AND SCORING* 



BERNARD B. BROWN** 



Summary. A brief description of the procedure followed in the Hollywood 
studios in scoring and prescoring motion picture productions. Scoring is the addi- 
tion oj music and effects after the finish of the photographing; prescoring is the prep- 
aration of musical or dance numbers before the photographing. 

PRESCORING 

The recording of music for motion pictures is divided into two 
categories: prescoring and scoring. As the name implies, pre- 
scoring means the recording of musical or dance numbers before the 
numbers themselves are actually photographed. At first thought, 
the idea of recording a sequence prior to photographing it may 
seem strange; but in actuality there are two very logical reasons 
for the sound director to do just that: (1) We prefer to make 
these recordings on a stage that has been acoustically treated to 
make it as perfect as possible for music recording. (2) By so doing, 
we are able to achieve not only fidelity of tone, but also of tempo. 

Our first reason is self-explanatory; our second is quickly explained. 
If we were to record a musical number as the director photographs it, 
we should be dealing with small sections of music, which when as- 
sembled would not be smooth, for the director breaks the sequence up 
into its component photographic parts, such as long shots, medium 
shots, close-ups, and various camera angles. It is obviously im- 
possible to play the music at exactly the same tempo each time 
these short scenes are photographed. Therefore, to do the job cor- 
rectly the musical number is first recorded on film and on a record, 
thus insuring that an even tempo will be maintained. It is well to 
point out that the artist, when making this recording, is free to make 
all the grimaces and contortions he feels may be necessary to reach 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received April 
25, 1942. 

** Universal Pictures Company, Inc., Universal City, Calif. 
228 



PRESCORING AND SCORING 229 

the high notes and pronounce the words clearly, as he is not being 
photographed while singing for this recording. 

The record is then taken to the sound stage and played back to the 
artist. Here the artist must look his (or her) best, which now is pos- 
sible because he does not have to think of the singing but only of 
looking well and synchronizing the lip movement to the record that 
has already been niade. He only has to appear as if he were singing, 
as the prescored record is used for the final film. 

On the scoring stage is a small room, 10 X 10 X 10 feet in size, in 
which the artist sings. A large window in one of the walls faces the 
orchestra so that the artist and the musical director can see each 
other. The singer can hear just enough of the orchestra to assist in 
singing in tune, but the sound of the singer's voice does not penetrate 
through to the stage, so the director uses ear-phones bridged into the 
vocal channel. As soon as a piece has been sufficiently rehearsed, 
all is ready for a take. The "quiet" signal is given, the stage man 
signals the recordist to start his machine, the red light flashes, the 
orchestra plays, the singer sings, and "Take Number One" is made. 

The musical number is recorded on two or more separate films and 
on a wax record which is played back so that the artist and others 
may hear and criticize the recording. If everyone is satisfied, the 
"take" is finished; if not, repeat recordings are made until a good one 
results or until there are enough good parts of several takes to cut 
together and make one good complete take. 

The orchestra and artist may then be dismissed. If after assembling 
the good parts of several takes the result is not entirely satisfactory, 
the singer is called back to the scoring stage to re-make all or part of 
the number. This is done by having the artist sing while listening 
on a pair of headphones to the orchestra track that has already been 
recorded. This process saves the studio thousands of dollars a year, 
since the orchestra is not required for retakes. 

When photographing dance numbers the recording that has been 
pre-scored is played back and the dancers perform to it. If the 
number is a tap dance the taps are recorded later on a special dance 
floor on the recording stage. The dancers are brought in and the 
picture of the dance that has been photographed is projected. The 
performers then dance while listening to the music through head- 
phones, and the taps are recorded. The picture has been cut ex- 
actly the way it appears in the theater, and the taps match the picture 
exactly. 



2:iO B. B. BROWN [j. s. M. P. E. 

SCORING 

Scoring is sometimes called "underscoring," which means adding 
music to the picture after it has been finished. The musical director 
and his associates view the finished picture with the producer or 
director, and decide where music can most effectively be used. While 
the musical director is composing the themes his assistant is timing 
the scenes, so as to know how much music to write and at what 
points it must synchronize with the action. 

Where it is necessary to time the music to several definite cues, a 
"click track" is made, which when reproduced sounds like a metro- 
nome. The "clicks" or beats range from one every sixteen frames to 
as many as one to every four frames. The tempo is determined by 
the tempo of the scene, and is produced by making a scratch or punch- 
ing a hole in a piece of blank film at the points where the beats are to 
occur. 

The film is then run on a moviola, and along with the picture, and 
on it are marked the cues in the picture to which the music must be 
made to fit. 

Now that the composer has the length of the scenes and the timing, 
he composes the music for the picture. The compositions then must 
be arranged, sometimes by the composer himself and sometimes by 
professional ' ' arrangers. ' ' The arrangement is checked by a musician 
called a proof-reader, who corrects any mistakes made by the com- 
poser or arranger, and the score is given to copyists who copy on sepa- 
rate sheets the music for the different instruments in the orchestra. 
The proof-reader again checks what the copyists have done, and all is 
now ready for recording. 

The orchestra is seated in a semicircle in front of the director, who 
stands upon a platform facing the screen and the musicians. The 
orchestra is arranged in sections with a microphone in each section, 
as follows, beginning at the left of the director: violins first, then 
violas and cellos, woodwinds, piano, bass, guitar, and harp, with the 
brass and the percussion instruments up in back on a separate plat- 
form. There are two principal reasons for using this arrangement : 
One is to provide good compositions and variety in the integrated 
sounds, just as the cameraman in photographing resorts to long shots, 
medium shots, and close-ups. The microphones used in the various 
sections pick up sound from both sides. They are tilted so as to have 
a close pick-up on one side and a long pick-up on the other side, and 
thus give good definition, room tone, and scope to the orchestra. 



Oct., 19421 PRESCORING AND SCORING 

The other reason for using a microphone in each section is to penm t 
the sound director to control the volume from each section by dials on 
his mixing panel in the monitoring booth. The volume of any section 
can be increased or decreased, so that if a section is too loud or too soft 
corrections can be made during the recording and a retake avoided. 
This saves much time, and time means money in the studio. 

The musical director now rehearses the orchestra and at the same 
time the sound director adjusts his levels on the mixing panel in the 
monitor booth. When all is ready the recording room is signalled, 
the picture is flashed on the screen, the orchestra plays, and the direc- 
tor conducts the orchestra while listening to the click track or dialog 
on a pair of headphones and looking at the picture on the screen be- 
hind the orchestra. The process is repeated for each section of music 
to be used with the picture. 

This describes briefly the general processes of prescoring and scor- 
ing. A thousand details have been omitted, and it must be em- 
phasized that the processes are not matters of simple routine. Each 
take has its own problems, and experience and experimentation are as 
much parts of the work as the general routine that has been described. 



A STUDY OF FLICKER IN 16-MM PICTURE PROJECTION* 

E. E. MASTERSON AND E. W. KELLOGG** 



Summary. It seems to be generally accepted opinion that three-blade shutters 
must be employed to control flicker properly in the projection of 16-mm pictures, even 
though the machine is not required to operate at less than 24 pictures per second. 
There is little complaint of the flicker in theater projection, where two-blade shutters 
are practically universal. Why then should it be necessary to make a large sacrifice in 
screen brightness by using three-blade shutters when projecting 16-mm pictures? Less 
control of the conditions of projection is probably the most important of the valid ob- 
jections. However, the opinion that two-blade shutters are not to be considered is based 
in part upon misleading tests, and the writers hold that for many applications single- 
speed machines should be given the benefit of the greater luminous efficiency possible 
with two-blade shutters. 

The paper discusses the various factors that bear on flicker, and reports a number of 
experimental studies. 

The Problem. For many years it has been the practice to project 
35-mm pictures in theaters at 24 frames per second with two 90- 
degree shutter blades, giving a 48-cycle flicker with equal dark and 
light intervals. It is customary, on the other hand, to equip 16-mm 
projectors with three-blade shutters, and this is at serious cost in 
screen brightness. The gain in light from substituting a two-blade 
for a three-blade shutter is shown in Table I. The gain depends 
upon the blade width, which in turn depends upon the pull-down 
time of the intermittent movement. 



Shutter 
Blade 



TABLE I 
Light on Screen 
3 Blade 2 Blade 



Ratio 



45 


0.652 


0.75 


1.20 


50 


0.585 


0.72 


1.22 


60 


0.50 


0.67 


1.33 


75 


0.375 


0.585 


1.56 


90 


0.25 


0.50 


2.00 



* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received May 4, 
1942. 

'* RCA Manufacturing Co., Indianapolis, Ind. 
232 



FLICKER IN 16-MM PICTURE PROJECTION 

The requirement that the flicker rate be 72 cycles per second for 
16-mm projection, whereas 48 cycles is considered satisfactory in 
theaters, is the more surprising when we consider that in the projec- 
tion of 16-mm pictures it has been common to use a pull-down that 
operates over a smaller fraction of the picture cycle; for example, 
about 60 degrees instead of the 90 degrees which is necessary with 
the Geneva motion generally employed in 35-mm machines. It is 
well known that the smaller the fraction of time that the screen is 
dark, the less noticeable is the flicker. Thus, flicker would be less 
with two 60-degree blades than with 90-degree blades. Therefore 
48-cycle flicker should be less noticeable in 16-mm pictures than in 
35-mm pictures. 

The obvious explanation of the prevalence of three-blade shutters 
in 16-mm projectors is that the machines are designed for projecting 
pictures at either 16 or 24 frames per second. In view of the vast 
number of silent 16-mm films, made at 16 frames per second, it seems 
clear that general-purpose projectors for a long time to come will 
have to meet this requirement and there seems to be no satisfactory 
solution to the flicker problem at this picture frequency except to 
use three blades. On the other hand, the increasing use of sound 
pictures is unquestionably bringing a market for projectors that will 
have to operate at only one speed. Under these conditions it becomes 
a question of considerable importance whether it is necessary to 
provide these projectors with three-blade shutters. The loss of 
between a quarter and a third of the available light is serious if it is 
not necessary. Tests have been made from time to time under 
varying conditions, with the usual verdict that the 48-cycle flicker 
is noticeable, whereas the three-blade shutter does away with flicker 
entirely. The result has been the continued use of the three-blade 
shutter. The anomaly that a projector with 48-cycle flicker is good 
enough for a theater, even the best, but not for 16-mm projection, 
has been a puzzle of long standing. The reluctance of many en- 
gineers to accept this conclusion (which seems so illogical) appeared 
to the writers to warrant a survey of the considerations applying to 
the problem, and experimental checks of some of the factors. 

Tests Using Screen without Picture or with Abnormally Bright Pic- 
tures. The first question that arises in attempting to make com- 
parisons between flicker under 35-mm and 16-mm projection condi- 
tions is, "What is the screen brightness at which the observations 
were made?" The relations between screen brightness and flickrr 



234 



E. E. MASTERSON AND E. W. KELLOGG [J. S. M. P. E. 



rate are shown in Fig. 1 which is reproduced from a paper by E. W. 
Engstrom on television image characteristics. 1 

Screen brightness of the order of 10 foot-lamberts 2 (without picture 
but with shutter running) is recommended for satisfactory picture 
projection, and is readily obtained with 16-mm projectors, provided 




A. ONE FRAME CYCLE (96O) 
0. LIGHT OPENING 



6 A 



6RI6HTNCSJ IN FOOT LAM6CRT5 
3 .6 .75 1.9 3 %9 6 7.ST I* 




-JU. 



0.5 f.O 2 3 ** 5 10 20 

SCREEN ILLUMINATION IN FOOT CANDLES 

FIG. 1. Relations between screen illumination, flicker frequency, and 
blade angle for threshold flicker. (Curve 5 corresponds to two 90-degree 
blades; Curve 6 to two 60-degree blades.) 

the screen size is not abnormally large. When the question of 
flicker is brought up the most natural way to make an observation 
is simply to run the machine without a picture and decide whether 
there is too much flicker. The result of such a test is almost invari- 
ably that the 48-cycle flicker would be objectionable, but the test is 
by no means a fair one. Theater practice is not based upon such a 
test but upon the very practical test of experience while viewing the 



Oct., 1942] FLICKER IN 16-MM PICTURE PROJECTION 



2.35 



pictures. When a picture is being projected the evidence of the 
flicker is very much reduced by several causes. Measurements with 
a number of typical pictures, including outdoor scenes, indicated 
average or integrated screen brightnesses ranging from 8 to 28 per 
cent of that of the blank screen, with an average of about 10 per 
cent; and highlight or white object brightness ranging from 50 to 
70 per cent. It might be thought that the tolerance for flicker would 
be determined entirely by the highlight intensity, but tests indicate 
that the area of the bright parts of the picture is also an important 
factor. Fig. 2 shows the results of a number of observations of the 



INCIDENT FOOT CANDL 
FOR THRESHOLD FLICKC 

H M P ? 

<M O * O <J 




























, 















d 








j 





u-: 


- 




P* ^^ 


^J 


* 










VIEWING 



X 3 * 8 T 
DISTANCE IN SCREEN WIDTHS 



FIG. 2. Effect of angle subtended by illuminated 
area upon flicker threshold (each form of symbol is for 
one observer). 

effect of viewing distance upon the value of screen brightness for 
just-perceptible flicker, using a blank screen. The farther the ob- 
server is from the screen, and therefore the smaller the angle sub- 
tended by the screen from his viewpoint, the greater is the flicker 
intensity that can be tolerated. It is a decidedly exceptional picture 
in which a bright highlight occupies l /* of the screen area. Where 
large areas of sky are shown, artistic photography would almost 
invariably resort to breaking up the expanse of clear sky with clouds, 
which means considerable darkening of much of the sky area. 

Another effect of the presence of the picture is that attention 
tends to be directed toward some center of interest. In viewing 
a blank screen the eyes wander from one part of the area to another. 
Flicker is much more noticeable with the eyes in motion than when 
the observer looks steadily at one part of the area (see Table II). 



236 E. E. MASTERSON AND E. W. KELLOGG [J. S. M. P. E. 

In addition to the effects of the picture just mentioned, we must 
recognize that picture jump is not completely eliminated, that there 
is jerkiness in all motion, and that these and other imperfections 
tend to mask what might otherwise be a perceptible flicker. 

Part of our recent study was an effort to make a rough deter- 
mination of the relation of flicker thresholds with and without pic- 
tures. Two projectors were arranged side by side, one with a shutter 
having three 70-degree blades and one with two 70-degree blades. 
Removal of the reflector from the 48-cycle machine gave substantial 
screen brightness balance. Loops of film showing the same subject 
were put into the machines and a number of observers were asked 

TABLE II 

Effect of Picture upon Flicker Tolerance (Foot- Candles for Unobjectionable Flicker} 

Still Blank Screen 

Picture Moving Eyes Fixed Eyes 

Observer Color* Picture* at Center Moving 

RLH 11 10.5 2.0 1.5 

LTS 9 13 4.8 2.0 

EWF 10 10.5 3 2.0 

HER 9 12 2.5 1.3 

CC 14 8 4.2 2.0 

HH 10 12 2.0 1.2 

* Illumination adjusted for satisfactory flicker with picture in place and mea- 
sured with picture removed. Screen reflectivity about 90 per cent. The angle 
subtended by the picture width was 18 degrees for still pictures, and 22 degrees 
for the motion pictures and blank screen tests, corresponding to observer dis- 
tances of 3.1 and 2.6 screen widths, respectively. 

to say whether they saw any more flicker in one than in the other, 
after as many switchings back and forth as they wanted. The 
distance of the screen from the projector was varied until the mini- 
mum distance (maximum brightness) was found at which the ob- 
server found no appreciable preference for the 72-cycle picture. The 
film was then removed from the projector and the screen illumination 
measured. Since the observer sat close beside the projectors, the 
angle subtended by the picture was not altered by distance. 

In another test a slide-projector was used with a shutter inter- 
rupting the light-beam. The shutter had two 60-degree blades, 
giving 48-cycle flicker. Numerous slides (in color) were introduced 
and the distance of the screen from the projector changed until the 
point was found at which flicker was not noticeable with the brightest 



Oct., 1942] FLICKER IN 16-MM PICTURE PROJECTION 237 

pictures. For comparison the screen illumination at which flicker 
practically disappeared was measured with no picture, first with the 
gaze directed continuously at the center of the screen and then with 
the eyes moving. Table II shows the results of these tests. 

The mean density of the slides was measured, using the Weston 
illumination meter and a K-2 Wratten filter to simulate roughly the 
color-sensitivity characteristic of the eye. These measurements 
indicated about the same average or integrated light transmission as 
the black-and-white 16-mm subjects, namely 28 per cent as a maxi- 
mum, with most of the subjects in the region of 10 per cent. 

The Committee on Non-Theatrical Equipment in its July, 1941, 
report 2 recognized the effect of the picture in reducing flicker, in 
specifying 3 foot-lamberts for bare-screen flicker tests, whereas they 
recommended 10 foot-lamberts as the desirable screen brightness 
for picture projection conditions but with no film in the machine. 

We have spoken of the misleading results of tests and demonstra- 
tions with the bare screen, without making due allowance for the 
effect of the picture. It is also easily possible for persons not too 
well acquainted with projection problems to be mislead by observa- 
tions with excessively bright pictures, especially if viewed from 
nearby. Such excessive brightness is easily possible in individual 
tests by projecting very small pictures. Beaded and metallized 
screens 3 may give bright spots having many times the luminous 
intensity shown by a good matte screen. If the actual service for 
which a projector is intended includes use with directive screens, a 
three-blade shutter is obviously in order. Our purpose here is 
simply to mention the fallacy of drawing conclusions from tests with 
directive screens and applying these conclusions to the case of matte 
screens. 

Effect of Color of Light Since theater pictures are projected with 
arc lamps, and 16-mm pictures for the most part with incandescent 
lamps, it occurred to the writers that the eye might be more sensitive- 
to flicker near the red end of the spectrum than near the blue end. 
The relations between color, brightness, and flicker have been the 
subject of many investigations 4 - * 6 7 but not being completely 
satisfied that the tests reported in the literature applied exactly to 
the problem under consideration here, the authors carried out a 
series of tests. In order to make any comparison it would be neces- 
sary to establish the fact that the screen brightness was equal for 
the two colors being compared. It was obviously not appropriate 



238 



E. E. MASTERSON AND E. W. KELLOGG U. S. M. P. E. 



to make the measurement of brightness with a photocell or photronic 
measuring device unless the spectral-sensitivity curve of the instru- 
ment was the same as that of the eye. To test the relative flicker 
sensitivity to lights of different color it was necessary, after selecting 
the desired color-separation filters, to rate the light projected through 
them in terms of its utility for visual purposes. In order that the 
eye adaptation 5 ' 6 might be representative of conditions during the 
viewing of motion pictures, a small spot of colored light was pro- 
jected on a test-object in the center of a rectangle which was illumi- 
nated from the rear, to about normal screen brightness. The first 
determinations of the illumination value of the light passing the 
several filters were made by measuring the light-flux on a Weston 



i 



FIG. 3. Relative response of the eye to light of 
various colors. 



photronic cell required for bare visibility of a dark test-object of low 
contrast. We then decided that it would be a better test of the 
general utility of the light to bring up the intensity until a test-object 
of extremely low contrast was just discernible. These readings gave 
the ratio between the light as measured by the photronic cell and its 
utility to the eye for visual purposes. The screen illumination at 
which flicker became just discernible also was determined for the 
same observers, and the ratio of measured illumination for threshold 
flicker and threshold visibility was compared for the several colors. 
The conclusion from these tests was that the sensitivity to flicker 
is in direct proportion to the brightness which makes for visibility 
and low-contrast discrimination. Since the photronic-meter mea- 
surement was in each case used for comparing two effects of the light 
of each color, the spectral sensitivity of the cell cancels out. As a 



Oct., 1942] FLICKER IN 16-MM PICTURE PROJECTION 239 

check, the visual density of the several color-filters was measured on 
a Capstaff densitometer. The work just described checks the con- 
clusions of various previous investigations. The well known flicker- 
photometer, for example, evaluates lights of different color in terms 
of the amount of flicker that they produce. Thus, when the flicker 
of a green light cancels that of a red light they are regarded as equal. 
In numerous investigations the results of flicker-photometer mea- 
surements have been compared with those of other types of photo- 
meter and the agreement has been found to be excellent. The well 
known eye-sensitivity curve (Fig. 3) has been checked by the three 
fundamental methods, judgment of brightness, flicker, and visibility, 
with substantially identical results. 4 ' 6>6 7 

From the foregoing it is evident that if two screens are equally 
satisfactorily illuminated but by light of slightly different color, 
flicker will be no more noticeable in one than in the other. There is, 
however, an error that may easily be made in comparing theater 
screen brightness with 16-mm screen brightness. Although foot- 
candle meters are designed to approximate eye-sensitivity, many 
of them are relatively more sensitive to blue light than the eye. If 
such a meter indicates an illumination of 10 foot-candles on a theater 
screen and 10 foot-candles on a 16-mm screen, the latter would 
actually look brighter to the eye. It is thus improper to compare 
the flicker on the basis of equally measured screen brightness unless 
the meter is corrected to match closely the spectral sensitivity of 
the eye. 

A psychological factor may enter into the judgment of screen 
brigthness as seen in theaters and in 16-mm projection. We asso- 
ciate high-intensity light-sources with very white or bluish light, 
and may thus be inclined to estimate the brightness of an arc-lighted 
screen as higher than that of an incandescent-lighted screen having 
the same useful brightness. In addition to this, the better sup- 
pression of stray light in the theater, of course, makes a given screen 
intensity seem greater than it would in the presence of more stray 
light. 

Effect ofA-C Ripple. During tests of the effect of speed of cutting 
we were interested in the actual "wave-shape" of the illumination 
curve. A cathode-ray tube was connected to the output of a photo- 
cell. This showed that, in addition to the effects of the shutter, 
the 120-cycle ripple in the lamp brightness was contributing to 
flicker effects. We estimated that the light from the 750-watt 



240 



E. E. MASTERSON AND E. W. KELLOGG [J. S. M. P. E. 



projection lamp fluctuated through a total range of about 5 per cent. 
E. E. Masterson devised the method shown in Fig. 4 of illustrating 
the effect of this upon flicker. In each x /24 second there are five 
periods of higher and five of lower lamp brightness. The effect of 
cutting off certain fractions of the cycle by the shutter-blades may 
result in an unbalance which produces a small component of 24- 
cycle flicker. The tolerance for flicker of this frequency is, of 
course, very small. It appears also that there are certain blade- 
widths that are better than others in reducing the 24-cycle compo- 
nent to a minimum. 

Effect of Blade Angle. Fig. 1 summarizes in useful form the relation 
between flicker frequency, screen illumination for flicker threshold, 



I20~ 





FIG. 4. Unbalance of 120-cycle fluctuation in lamp 
brightness, produced by shutter blades. 



and ratio of bright to dark time. Screen illumination was measured 
with the shutter running. The reflectivity of the test-screen was 
given as 75 per cent, whence the brightness in foot-lamberts would 
be 0.75 of the foot-candles read on the vertical scale. It will be 
noted that narrowing the shutter-blades makes it possible to work 
with greater screen brightness without observaole flicker. The 
increased efficiency may be used in part for increasing screen bright- 
ness and partly for reducing lamp wattage or simplifying the optics. 
From Fig. 1 it is clear that we can not classify flickers in terms of the 
frequency only but must specify the bright to dark ratio, or blade- 
width, in addition to the number of blades and the mean screen 
brightness. With two 60-degree blades, Fig. 1 indicates that 10 
foot-candles, or 7.5 foot-lamberts would give threshold flicker on a 



Oct., 1942] FLICKER IN 16-MM PICTURE PROJECTION 241 

bare screen at 48 cycles. The observations upon which these curves 
were based were with a 14 X 16-inch bare screen six feet from the 
observer. 

Effects of Speed Of Cutting. It seems reasonable to expect that a 
shutter system that maintained full brightness up to the last possible 
instant, and then cut off quickly, would give less flicker than one 
with which the screen was at its maximum brightness only during 
the middle of the bright period. To test this, a projection system 
was arranged with a large-diameter shutter that could be placed at 
chosen positions in the light-beam and could be used either with its 
axis fairly close to the optical axis or farther away, so that the blade 
edges were moving faster. The light-beam was about 1 inch in 
diameter at the largest and about 3 /s inch in diameter at the smallest, 
and the 24-rps shutter was used with from 2 to 4-inch active radius. 
Within the range of these tests no noticeable difference was found 
in the screen brightness for threshold. We do not consider that this 
proves that the wave-form of the screen-brightness curve is immate- 
rial, but it is safe to say that it does not affect the flicker radically 
and there is every practical reason for maintaining the screen bright- 
ness at full possible value for the longest possible time. It is of 
course of even greater importance to cut the light off completely 
during the time that the film is in motion. 

Since the light-beam is at its smallest cross-section close to the 
picture aperture, quick cutting is promoted by placing the shutter 
close to the aperture. The gain, however, may not be quite in 
proportion to the reduction in distance across the light-beam. With 
a focal-plane shutter the entire picture is not obscured at the same 
instant, and any portion that is not covered while the film is moving 
is on the screen at full brilliance. The avoidance of travel-ghost 
may therefore require more complete fulfillment of the requirement 
of complete coverage during motion than seems to be necessary with 
the shutter farther away where it acts to fade the entire picture in 
and out. 

Tests were made to determine whether there is any difference in 
noticeable flicker with a focal-plane shutter as compared with a lens- 
aperture shutter, the blade size being identical. No difference 
could be noticed. 

Shutters with Unequal Blades. Trials have been made from time 
to time of shutters with various arrangements of unequal blades in 
the hope of finding an arrangement that would permit the necessary 



242 E. E. MASTERSON AND E. W. KELLOGG [J. S. M. P. E. 

blade-width to prevent travel-ghost and not intercept so much light 
while the picture is stationary as the usual full- width extra blades. 
In 1938 R. O. Drew conducted a series of experiments using a shutter 
with one full-width and two narrower blades. The narrow blades 
could be shifted in position. The optimal position was found (within 
the limits of observations) to be that at which the shutter is also 
mechanically balanced. If the light-intensity is plotted as a wave, 
a Fourier analysis shows that the abovementioned condition results 
in the fundamental component's becoming zero. In other words 
there is no 24-cycle component of flicker. However, it is not beyond 
possibility that the eye response is of such nature that the actual 
optic nerve stimulation would have a component of fundamental 
frequency even though the external stimulus did not have it. This 
would be analogous to the well known reconstruction of fundamental 
frequency due to the non-linear character of the ear. In these tests, 
which were made with a blank screen, the observers judged the 
flicker produced by the shutter with the three unequal blades to be 
about as objectionable as the 48-cycle flicker from a balanced two- 
blade shutter. In recent tests, however, the conclusions from a 
fairly large number of observations was that when a picture is being 
shown- the flicker from the unequal-blade shutter can, if the shutter 
is properly designed, be substantially less than with a two-blade 
shutter. The unbalanced shutter therefore represents a compromise 
between the two- and three-blade shutters, and evidently has a place 
in picture projection. 

Conclusions. Omitting from consideration the obvious necessity 
of using a three-blade shutter if the same machine must also project 
pictures at 16 pictures per second, the widely held opinion that three- 
blacfe shutters are needed for 16-mm picture projection (at 24 frames 
per second) whereas the two-blade shutters apparently give satis- 
faction in theaters may be attributed to the following: 

(1} Many of the comparisons have been made with no picture in the machine, 
or with the screen so close to the machine that the picture was much brighter than 
that corresponding to ordinary projection. ' 

(2} In comparing theater conditions with 16-mm projection conditions, it may 
frequently have been considered that the screen brightnesses were equal, because 
so indicated by a foot-candle meter, whereas from the visual standpoint the 16-mm 
film was actually brighter. The better freedom from stray light and the whiter 
character of the screen illumination probably gives theater patrons an impression 
of abundant brightness whereas the same actual screen illumination under 16-mm 
projector conditions would seem to be less bright. 

(5) Although the only logical way of measuring screen brightness is in terms of 



Oct., 1942] FLICKER IN 16-MM PICTURE PROJECTION 243 

the reflected light (foot-lamberts), measurements of the incident light are com- 
mon. The reflectivity of theater screens is cut down slightly by the perforations. 
Therefore the actual brightness tends to be less, for the same illumination, in a 
theater than in a 16-mm projecting system, assuming the screens to be of equal 
quality. 

(4) The 120-cycle fluctuation in lamp brightness may under some conditions 
increase the flicker effect. 

(5) The eye is more sensitive to flicker at the beginning of a period of watch- 
ing motion pictures than after a few minutes of continuous viewing. Therefore 
practically all tests for flicker threshold (and this includes our own tests recorded 
here) give lower values of brightness for threshold flicker than those that would 
correspond to freedom from noticeable flicker during most of the duration of a 
film showing. The subject of flicker fatigue and adjustment to flicker was inter- 
estingly discussed by P. A. Snell, 8 in the May, 1933, JOURNAL. 

(6) It is more than likely that if a comparison were arranged under theater 
conditions with a two-blade shutter in one machine and a three-blade shutter in the 
other and with the screen brightness equalized to normal level, the observers 
would see a perceptible difference. In other words we probably tolerate per- 
ceptible flicker in theaters. Owing to the ease with which tests and comparisons 
can be made, we have become more critical in the 16-mm field. 

(7) Screen brightness in the theater and viewing distances are the same from 
day to day. The inability to control or predict conditions of use constitutes a 
valid reason for providing against more severe conditions of showing in the case of 
the 16-mm projectors. 

The following items of interest in connection with flicker studies 
have been brought out in our recent tests : 

(1) Tolerance for flicker increases in marked degree after the first few minutes 
of continuous viewing. Some of the tolerance is probably developed within a 
few seconds, as is evidenced by the reduced sensitivity to flicker when the eyes do 
not move. 

(2) Color of the light may be a factor in creating a subjective impression (prob- 
ably based upon association) of differences in screen brightness, but in terms of 
visual utility the flicker threshold and useful brightness go together independ- 
ently of the color of the light. 

(3) When a picture is being projected the average screen brightness is a small 
fraction of that of a blank screen, and even the bright portions are likely to be 
little more than half the maximum possible brightness. This means that picture 
projection will be satisfactory even though the illumination of the bare screen may 
be three or four tunes flicker threshold. 

(4) It is permissible to allow the screen brightness in small areas of the pro- 
jected picture to exceed considerably the blank-screen flicker threshold. This is 
because the viewing angle subtended by the bright area is a large factor. 

(5) When viewing a large area, the sensitivity to flicker is much increased by 
the motion of the eye. 

. (6) The magnitude of the flicker is not materially affected by the location of 
the shutter or the velocity of the edge of the blade, but the blade-width is im- 
portant, and the narrower the blade the better. 



244 E. E. MASTERSON AND E. W. KELLOGG 

(7) The value of high blade-speed (or large radius) is that it will permit the 
use of a narrower blade without travel-ghost. 

The general conclusion from our studies is that the decision to 
employ three-blade shutters for general-purpose 16-mm projectors 
where the conditions of use can not be predicted, is entirely justified. 
Projectors with three-blade shutters and with incandescent lamps 
can, if provided with efficient optical systems, illuminate a 3 X 4- 
foot screen with 10 foot-candles. Hence with screens of this size 
or smaller, two-blade shutters can not be recommended as giving 
any better picture. On the other hand, projectors that are designed 
to be used for showings to fairly large audiences, where screens 5 
feet or more wide are desirable in order to make the picture easily 
seen from the remote seats, should (if they are not equipped with arc 
lamps) preferably have two-blade shutters in order to obtain the 
benefit of the brighter picture. Unless the screen brightness (with 
no picture in the machine) considerably exceeds 10 foot-lamberts, 
flicker should be no worse than it is in practically all theaters. 

REFERENCES 

1 ENGSTROM, E. W.: "A Study of Television Image Characteristics," Part II, 
Proc. IRE (April, 1935) ; "Television," Vol. I, RCA Institutes, 1936. 

2 Report of the Committee on Non-Theatrical Equipment, J. Soc. Mot. Pict. 
Eng., XXXVII (July, 1941); (Recommended Screen Brightness, p. 31) (Flicker 
Tests, p. 60). 

3 Report of Committee on Non-Theatrical Equipment, /. Soc. Mot. Pict. Eng., 
XXXVII (July, 1941); (Optical Properties of Screens, p. 47). 

JONES, L. A., AND FILLIUS, M. F.: "Reflection Characteristics of Projection 
Screens," Trans. Soc. Mot. Pict. Eng., No. 11 (1930), p. 59. 

JONES, L. A., AND TUTTLE, C.: "Reflection Characteristics of Projection 
Screens," Trans. Soc. Mot. Pict. Eng., No. 28 (Feb., 1927), p. 183. 

LITTLE, W. F.: "Tests of Motion Picture Screens," /. Soc. Mot. Pict. Eng., 
XVI (Jan., 1931), p. 31. 

Report of the Projection Screens Committee, J. Soc. Mot. Pict. Eng., XVII 
(Sept., 1931), p. 441. 

LYMAN, D. F.: "Relation between Illumination and Screen Size for Non- 
Theatrical Projection," /. Soc. Pict. Eng., XXV (Sept., 1935), p. 231. 

4 Scientific Papers, Nos. 303 and 475, Nat. Bureau Standards. 

6 HARDY, A. C., AND PERRIN, F. H. : "Principles of Optics," McGraw-Hill Book 
Company, New York, Chapt. X. 

6 SOUTHALL, J. P. C. : "Physiological Optics," Oxford University Press, Chapt. 
X, p. 372. 

7 IVES, H. E.: "Spectral Luminosity Curves by the Method of Critical Fre- 
quency," Phil. Mag., 24 (1912), p. 352. 

8 SNELL, P. A.: "An Introduction to the Experimental Study of Visual 
Fatigue," /. Soc. Mot. Pict. Eng., XX (May, 1933). p. 367. 



DEVELOPMENTS IN TIME-SAVING PROCESS PROTECTION 

EQUIPMENT* 



R. W. HENDERSON** 

Summary. The projection of a motion picture on a translucent screen for back- 
ground purposes has become increasingly important in studio operations during the 
past ten years. Many shots now made through the use of this process would have been 
extremely costly and perhaps impossible if attempted by direct filming of the complete 
action. 

The sharp rise in production costs during the past few years, coupled with the cur- 
tailment of foreign markets, demanded that every effort be expended to simplify pro- 
duction methods. 

With this in view, Paramount Pictures embarked upon a complete modernization 
program of the Transparency department production equipment early in 1940. New 
compact projection units, bases for the projectors, rewind tables, screen frames, screen 
handling equipment, and light-bridges were designed and built. This equipment has 
immeasurably simplified operations as well as improved quality beyond levels hereto- 
fore achieved. 

Descriptions of this equipment are presented, with emphasis upon a comparison of 
the new with the old. The success of the equipment can be attributed largely to stand- 
ardization of component parts. Complete inter changeability of essential units, coupled 
with easy access to critical points, has gone far toward eliminating lost time and motion 
in meeting unexpected emergencies. 

The projection of a motion picture upon a translucent screen for 
background purposes has become increasingly important in studio 
operations during the past ten years. Directors and producers have 
come to accept these backgrounds with confidence in the appearance 
of the finished photographic illusion, where they once insisted 
upon location shots. Through the cooperation of these men and 
the efforts of the Transparency Division of Paramount's special photo- 
graphic department, headed by Mr. Farciot Edouart, techniques 
have been developed that permit the making of certain types of 
scenes that would have been impossible without the use of projected 
backgrounds. The importance of this work is more evident now 

*Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received April 
13, 1942. 

** Paramount Pictures, Inc., Hollywood, Calif. 

L'4. r . 



246 R. W. HENDERSON u. S. M. p. E. 

than ever before, because of the increased costs entailed in sending a 
shooting company on location. 

One of the greatest advantages of background projection is that 
of providing "cover" for a company that might otherwise be delayed 
by some unforeseen difficulty that may arise in spite of careful plan- 
ning. The most common of these is that of a company finishing a 
day's scheduled shooting early in the afternoon, in which case the 
cast would have to be dismissed on pay if it were not possible to move 
into a transparency scene. Realizing this, the production depart- 
ment attempts to maintain at least one transparency set as "cover" 
for every shooting company. 

The "stand-by" function of background projection set-ups de- 
mands that all the equipment used be of a standardized, interchange- 
able nature; flexible, efficient, easily handled by a minimum of 
operating personnel; and so arranged that it can be assembled and 
put into action in a few minutes. 

With this aim in view, the Paramount Engineering department, 
following a preliminary investigation period, commenced design work 
early in 1940 on a complete modernization program embracing the 
following major equipment used by the transparency department, 
which will be described in the order named. 

(I) Projection units 
(2} Projector bases 

(A) Single 

() Triple 
(5) Rewind tables 

(4) Screen equipment 

(A) Screen frames 

(B) Screen jacks 

(5) Light bridges 

(1) PROJECTION UNITS 

Customary studio practice during the last ten years has been to 
have the projection machine permanently housed hi a large, cumber- 
some, heavy booth which was awkward to move in and out of restricted 
stage space. In addition, the extreme heat from the arc lamp, 
cramped working space, excessive noise, and limited ventilation 
provided poor operating conditions for the projectionist. 

* Another objection to the booth was the difficulty of making high 
shots. To accomplish such shots, the booth had to be taken to a 
large hydraulic hoist on the lot, lifted, rolled off onto a caster base 



Oct., 1942] 



PROCESS PROJECTION EQUIPMENT 



247 



parallel, and pushed back upon the stage. This was not only time- 
consuming but hazardous when negotiating the ramps outside the 
stage doors. 

To eliminate these objections, Paramount followed the lead set 
by Selznick International Pictures in 1939 and embarked upon the 
design of a comparatively light-weight, silent, projection unit that 
could be used without a booth. In general, the specifications as 
drawn up by the Process Projection Equipment Committee of the 




FIG. 1. New type silent projector; operator's sidi 

Research Council of the Academy of Motion Picture Arts & Sciences 
were adopted. 

To increase flexibility further, the projector was designed as a 
complete unit in itself, comprised of a projection head, light-tube, 
optical relay condenser system, lamp house, self-contained cooling 
system, and a support housing that tied all these various elements 
together into one completely independent assembly that could readily 
be lifted on or off a separate base, as shown in Fig. 1. 

The projection head was designed and built by the Mitchell 
Camera Corporation in accordance with the suggestions of the Re- 



248 R- W. HENDERSON [j. s. M. P. E. 

search Council. To date eight of these heads have been built: one 
for Selznick International Pictures, Inc., three for RKO, and four 
for Paramount. 

The projection-head mechanism is driven by a 1440-rpm distribu- 
tor controlled, a-c interlock motor which is normally tied in with 
a camera and a recording machine. To provide for all "sync" shots, 
i. e., shots made without recording sound, a special variable -speed 
d-c driving motor was built into the top of the projection-head. 
When in use, this motor is connected through a magnetic clutch to 
the head mechanism and to the rotor of the interlock motor. By 
applying three-phase power from a common source to the stator 
windings of both the interlock motor arid the camera motor, the 
interlock motor becomes in effect a distributor interlocking the 
camera to the projector. 

For standard speed work the d-c motor operates at 1440 rpm, 
controlled by a centrifugal governor. The variable-speed feature 
was designed to provide for under 1 and over-cranking between the 
limits of 12 and 36 frames per second. 

This system eliminates the necessity of having a sound crew stand- 
ing by for the single purpose of operating the distributor in the re- 
cording building, or the equally objectionable practice of having a 
local distributor either on or just outside the stage. Another great 
advantage of the reversible d-c drive system is that it provides a 
rapid method of rewinding, particularly during line-up. 

The light- tube serves as a support for the projection-head and also 
as a housing for the relay condenser elements and fire-shutter. It 
consists of cylindrical Mehanite casting to the outer end of which 
the projection-head is fastened by a large-diameter clamping ring. 
This ring is fitted with a tangent-screw adjustment which permits 
rotation of the head about the optical axis for line-up purposes and 
special effects. This feature is a particularly important time-saver 
during the registration of superimposed pictures from several ma- 
chines in multiple-head projection. The lamp house is a Mole- 
Richardson type 250 designed in accordance with recommendations 
of the Research Council. 

The cooling unit consists of a motor, centrifugal pump, squirrel- 
cage blower, and radiator, mounted on rubber as an isolated unit 
under the lamp house. Its function is to supply cooling water to 
the carbon -holding jaws in the lamp house and to the jacket sur- 
rounding the distilled water in the water-cell of the optical system. 



Oct., 1942] PROCESS PROJECTION EQUIPMENT 

To 'increase the efficiency of the projection unit further, a talk- 
back amplifier system was added, terminating with the cameraman 
on the set in the form of a small combination microphone-speaker. 
Paralleling this system is another combination microphone-speaker 
mounted on a small portable desk just off the set which is normally 
tended by the assistant cameraman whose duty it is to keep the 
shooting log and print records. The desk is equipped with a remote- 
control panel, making it possible to operate the projector from that 




FIG. 2. Triple-head projection unit ; top view. 

point for special shots. It also contains a group of signal push- 
buttons for transmitting instructions to the projectionist without 
the aid of the talk-back system. 

High shots with the new equipment are normally made from 
parallels. For certain shots, however, where restricted stage space 
and the ability to make quick moves are the governing factors, the 
equipment may be rolled onto the platform of a compact motor- 
driven industrial stacker or telescoping elevator, the floor-space 
required by the stacker being only slightly greater than that of the 
projector and its associated equipment. 



250 



R. W. HENDERSON 



U. S. M. P. E. 



The performance of the unit can best be judged by the relatively 
high average light output level of about 42,000 lumens, which has 
been boosted to better than 50,000 lumens at times through careful 
regulation and operation. 



(A) 



(2) PROJECTOR BASES 

Single Projector Base. The single projector base serves as 



a mount for the projection unit and is a complete piece of equipment 




FIG. 3. Key operator's station, triple-head projection unit. 

in itself. Into it is built a panning mechanism permitting a 360- 
degree rotation about a vertical axis, a tilt-mechanism allowing a 
^20-degree tilt from the horizontal, and an elevating mechanism 
capable of placing the optical axis anywhere between 4 feet 9 inches 
and 6 feet 8 inches above the floor. The single bases built to date 
are completely interchangeable with any of the four projection units, 
thereby eliminating unnecessary confusion and delays that might 
otherwise affect set-up time. 

(B) Triple Projector Base. With the advent of large-screen color 
shots, the industry turned to multiple-head projection and super- 



Oct., 1942] PROCESS PROJECTION EQUIPMENT 251 

imposed pictures to increase the screen illumination. To provide 
for this type of work, a base was designed upon which any three of 
the four projectors could be mounted in approximately 45 minutes, 
including the time required to collect and lift them from their indi- 
vidual bases (Figs. 2 and 3). Built-in mechanisms in the base 
provide for =*=5-degree pan and tilt with the possibility of increasing 
this range through the auxiliary jacks used to tie off the base to the 
floor. This new equipment has an average total light output level of 




FIG. 4. New type projection unit, rewind stand, and working platform ; 

front view. 



about 126,000 lumens, replacing the old triple booth which had a total 
light output of slightly less than one of the new single-projection 
units. 

Most of Paramount's large-screen shots are made in an outdoor 
diffused area approximately 62 feet wide by 300 feet long. To 
increase further the flexibility of the triple-head unit in this location, 
the machine is placed on the floor of a semiportable elevator per- 
mitting a maximum optical axis height of 19 feet 6 inches above the 
floor. If the unit is required on any other stage, it can be rolled off 



252 



R. W. HENDERSON 



[J. S. M. P. E. 



the elevator, transported on its own wheels, and set up on its jacks 
wherever desired. 

The synchronized control of the triple-head motor system, neces- 
sary for superposition of pictures, is accomplished through a central 
control-panel permanently mounted on the base which gives the 
key operator control of all three machines when running in interlock. 
However, the individual projectionists can at will drop off the line 
and run independently for line-up and rewind if they so desire. The 




FIG. 5. New type 18' X 24' stressed-skin metal screen frame. 

built-in talk-back system mentioned above as a part of the projection 
unit serves in the same capacity in the triple set-up. 

(3) REWIND TABLE 

A necessary auxiliary to the projector is the rewind table, which 
serves the dual purpose of a storage cabinet for film, lenses, and 
operating equipment, as well as a work table for rewinding, cleaning, 
and examining the film (Fig. 4). 

This unit is of all steel construction and is normally mounted on a 
rubber-tired caster-equipped dolly having a built-on folding work- 



Oct., 1942] 



PROCESS PROJECTION EQUIPMENT 



253 



platform on which the projectionist stands. The work-platform, 
floor of the projector base, and floor of the rewind dolly are all at the 
same level, thereby producing an unobstructed working area from 
which the projectionist can reach either the table or the projector 
controls merely by turning around. 

The table top is equipped with standard manually operated re- 
winds, a flush-surface opal-glass panel illuminated by fluorescent 
light for scanning the film as it is rewound, and a folding- type flu- 




FIG. 6. New metal light-bridge; minimum span and height. 



orescent reflector for general illumination of the working area. 

When it is necessary to operate the projector from high parallels 
or on the elevator it would often be inconvenient to leave the rewind 
table mounted on its dolly. For shots of this type the table is nor- 
mally lifted off the dolly and used without the convenience of the 
work platform. 

With this new equipment, the operator has pleasant surroundings, 
compact, orderly arrangement of all accessories, and no appreciable 
mechanical noise, all of which is in marked contrast to the old system. 



254 



R. W. HENDERSON 

(4) SCREEN EQUIPMENT 



[J. S. M. P. E. 



The primary objection to the conventional transparency-screen 
frame and supporting structure has been its great bulk. Customary 
practice has been to have the screen frame permanently hung inside 
a portable bridge which served as a catwalk for the mounting of top 
lights. This procedure necessitated moving the large units on and 
off stages continually and was often complicated by the arrangement 
of sets on the stage. In some cases the day's work on one stage 




FIG. 7. New metal light-bridge; maximum span and height. 

would require two or perhaps three screen sizes, which meant that 
either a great deal of stage space was taken up by the units not in 
use or the sets had to be so arranged as to leave easy access to the 
door to permit exchanging the screens. 

To minimize the handling problem, a system was devised that 
incorporates a very light stressed-skin steel frame in which the screen 
is mounted, portable elevating-type jacks which can be readily 
attached to the ends of these frames for handling, and an independent 
light-bridge of semistressed-skin construction from which the screen 
frame can be hung if desired. 



Oct., 1942] PROCESS PROJECTION EQUIPMENT 255 

(A) Screen Frames. Four standard-size screen frames were 
designed using steel stressed-skin or the full Monocoque principle, 
as it is sometimes called. In this type of construction, the loads 
applied to the structure are carried principally by the thin sheet- 
metal covering, eliminating the necessity of having a relatively heavy 
internal structural framework, and thereby reducing the overall 
weight of the unit. To date the studio has acquired four 1 1 feet X 
14 feet, two 14 feet X 18 feet, two 16 feet X 21 feet, and four 18 
feet X 24 feet screens (Fig. 5). The frames are remarkably light 
and rigid, and can be used either on their own detachable jack sup- 
ports or can be hung from the light-bridge structure. 

One important feature of the frames is the minimum screen height, 
which places the lower edge of the working area within three to four 
inches of the floor. This feature permits building directly on the 
floor certain sets that previously had to be built on parallels. 

Some transparency shots can be made without heavy top-lighting, 
so for these shots the light-bridge previously mentioned can be dis- 
pensed with entirely. In the event that a small amount of overhead 
lighting is required, but not enough to warrant the use of a light- 
bridge, sockets have been provided along the top of the screen frames 
to take the spindles of the light-bails. For protection of the screen 
material during handling, light-weight plywood cover-panels of 
sectionalized design are hung from the top of the frame. One man 
can handle the largest panels, although two men usually work to- 
gether. 

An enclosed, moderately dust-tight storage shed with an overhead 
monorail system was built for the protection of the screens and other 
equipment when not in use. The monorail system makes it a simple 
matter for the operating personnel to select any of the twelve screens 
and move it out of the building. From that point it is transported 
on its own jacks to any stage on the lot, the entire procedure requiring 
only a few minutes. 

(B) Screen Jacks. The screen jacks are compact, easily handled, 
caster-equipped elevators which engage built-in lugs on the ends of 
the screen-frame. They are provided with a tow-bar, diagonal tie- 
rods for bracing to the screen frame, and a folding leg with third 
wheel for stabilizing the jack when not attached to the screen -frame. 
The jacks have a maximum lift of six feet, permitting the making of 
high shots without the expense of building special parallels for sup- 
porting the screens. 



256 R. W. HENDERSON [j. s. M. p. E. 

When in the high position, the wheel-base of the jacks can be in- 
creased by a built-in feature to provide all the necessary stability for 
safe operation. 

(5) LIGHT-BRIDGES 

The light-bridge illustrated in Figs. 6 and 7 is of semistressed- 
skin construction which gives it great load-carrying capacity in 
proportion to its weight. The bridge structure is designed to tele- 
scope in both directions. In the most compact position it has a net 
clear rectangular opening of 13 feet 3 inches X 18 feet 3 inches, 
which can be extended 13 feet 4 inches Vertically and 10 feet 
inches horizontally to a maximum opening of 26 feet 7 inches X 28 
feet 3 inches. This extended opening permits hanging an 18 feet X 
24 feet screen six feet in the air. All smaller screens can be hung 
wherever desired in the bridge opening. This construction is par- 
ticularly useful when the arrangement of the props might require a 
bridge that could completely straddle the set. 

The first of three of these light-bridges has recently been put into 
use. When the other two are completed it is planned to assign each 
to a group of about four stages among which it can be shuttled as 
required. This procedure should help considerably in minimizing 
handling and set-up time. 

The two remaining items included in the modernization program 
are the construction of a stereopticon projector, the design of which 
is substantially complete, and the design and construction of a high- 
speed motion picture background projector. 

The base for the high-speed projector will be identical to the other 
four single-bases, and the general appearance of the projection unit 
will be similar to that of the standard-speed machines. The differ- 
ence will be mainly in the design of the motor system and the projec- 
tion-head, which has been delayed by the war. It is intended that 
this unit be capable of overcranking as high as 120 frames per second, 
or five times normal speed, which is desirable for many types of 
miniature work. 

In addition to its primary high-speed function, it will be possible 
to operate the unit at 24 frames per second, thereby giving the studio 
a fifth-standard-speed projector if required during heavy shooting 
schedules. 

Stereo-projection is a potential source of considerable savings, 
both in the shooting of the original plates as well as in processing. 



Oct., 1942] PROCESS PROJECTION EQUIPMENT 257 

The plates can be taken by a still photographer working without the 
assistance of a staff of technicians, as contrasted to the procedure 
necessary when shooting motion picture backgrounds. Here it is 
necessary to send out a cameraman, an assistant, perhaps a camera 
mechanic, and a considerable amount of miscellaneous operating 
equipment that is particularly objectionable when travelling by air. 
In addition, there is the cost of the negative, processing, and print 
which must be met before the picture can be used. The resulting 
cost differential makes it desirable to use still backgrounds wherever 
possible. 

Paramount has used the process frequently but has been limited 
in recent years by design improvements and a higher standard of 
quality that outmoded the equipment available. It is believed that 
the new stereopticon that is about to be constructed will broaden 
the field of application for this type of equipment and permit con- 
siderable reductions in costs for still background work. 

With the completion of this new equipment, it is felt that Para- 
mount will be well equipped to cope with the changing production 
technique and operating conditions that will inevitably follow as an 
aftermath of the present world-wide conflict. 



CURRENT LITERATURE OF INTEREST TO THE MOTION PICTURE 

ENGINEER 



The editors present for convenient reference a list of articles dealing with subjects 
cognate to motion picture engineering published in a number of selected journals. 
Photostatic copies may be obtained from the Library of Congress, Washington, D. C. 
or from the New York Public Library, New York, N. Y. Micro copies of articles 
in magazines that are available may be obtained from the Bibliofilm Service, Depart- 
ment of Agriculture, Washington, D. C., at prevailing rates. 



American Cinematographer 

23 (Aug., 1942), No. 8 

"Pre-Photographing" in 16-Mm as a Means of, Conserv- 
ing Film (pp. 342-343, 382) 

Animated Cartoon Production Today. Pt. V (pp. 344- 
346, 380-382) 

Make 16-Mm Business Movies That Help the War Effort 
(pp. 347, 379-380) 

Controlling Color in Lighting 16-Mm Kodachrome for 
Professional Pictures (pp. 348-349, 377-379) 

Diopters for Distortion (pp. 358, 370-371) 

Explaining "Montage" (pp. 359, 364-366) 

Making Movies under Water (pp. 360, 370) 

Why Not Try Making Third-Dimensional Movies? (pp. 
362-363, 366-368) 



Institute of Radio Engineers, Proceedings 

30 (Aug., 1942), No. 8 

Recording and Reproducing Standards (pp. 355-356) 
The Zero-Beat Method of Frequency Discrimination (pp. 

365-367) 
Transients in Frequency Modulation (pp. 378-383) 

Motion Picture Herald (Better Theaters Section) 

148 (July 25, 1942), No. 4 
Simple Method of Testing and Correcting the Projection 

Light System (pp. 7-9, 19-20) 
Luminous Screen Frame (pp. 10-11, 20) 



L. GARMES 
C. FALLBERG 
W. G. Bosco 

J. A. LARSEN, JR. 
J. WALKER 
L. G. DUNN 
T. TUTWILER 

P. TANNURA 



L. C. SMEBY 

C. F. SHEAFFER 
H. SALINGER 



C. E. SHULTZ 

B. SCHLANGER 



258 



FIFTY-SECOND SEMI-ANNUAL MEETING 

OF THE 
SOCIETY OF MOTION PICTURE ENGINEERS 



HOTEL PENNSYLVANIA, NEW YORK, N. Y. 
OCTOBER 27th-29th, INCLUSIVE 

OFFICERS AND COMMITTEES IN CHARGE 

EMERY HUSE, President 

E. ALLAN WILLIFORD, Past-President 

HERBERT GRIFFIN, Executive V ice-President 

W. C. KUNZMANN, Convention Vice-President 

A. C. DOWNES, Editorial Vice-P resident 

ALFRED N. GOLDSMITH, Chairman, Local Arrangements Committee 

SYLVAN HARRIS, Chairman, Papers Committee 

JULIUS HABER, Chairman, Publicity Committee 

J. FRANK, JR., Chairman, Membership Committee 

H. F. HEIDEGGER, Chairman, Convention Projection Committee 

Reception and Local Arrangements 

ALFRED N. GOLDSMITH, Chairman 



R. B. AUSTRIAN 
L. A. BONN 
M. R. BOYER 
J. C. BURNETT 
F. E. CAHILL, JR. 
A. S. DICKINSON 
W. E. GREEN 
J. A. HAMMOND 
M. HOB ART 



J. FRANK, JR. 
G. FRIEDL, JR. 



L. W. DAVEE 
P. C. GOLDMARK 
R. F. MITCHELL 



C. F. HORSTMAN 
L. B. ISAAC 
E. W. KELLOGG 

J. H. KURLANDER 

P. J. LARSEN 
J. A. MAURER 
P. A. McGuiRE 
O. F. NEU 

J. A. NORLING 



WM. H. OFFENHAUSBR, JR. 

W. M. PALMER 

H. RUBIN 

V. B. SEASE 

T. E. SHEA 

E. I. SPONABLE 

J. H. SPRAY 

R. O. STROCK 

H. E. WHITE 



Registration and Information 

W. C. KUNZMANN, Chairman 
E. R. GEIB H. K. MCLEAN 



F. HOHMEISTER 



P. K. SLEEMAN 



Hotel and Transportation 
O. F. NEU, Chairman 



W. M. PALMER 
P. D. RIES 
C. Ross 



J. A. SCHBICK 

F. C. SCHMID 

E. S. SBBLBY 



800 



260 



G. GIROUX 
C. R. KEITH 



FALL MEETING 

Publicity Committee 

JULIUS HABER, Chairman 
SYLVAN HARRIS 



[J. S. M. P. E. 



P. A. McGuiRE 
F. H. RICHARDSON 



M. R. BOYER 
J. C. BURNETT 
P. C. GOLDMARK 
ALFRED N. GOLDSMITH 



MRS. M. R. BOYER 
MRS. A. S. DICKINSON 
MRS. J. FRANK, JR. 
MRS. G. FRIEDL, JR. 
MRS. P. C. GOLDMARK 



F. CAHILL, JR. 

T. H. CARPENTER 
L. W. DAVEE 

G. E. EDWARDS 
J. K. ELDERKIN 



Luncheon and Banquet 

D. E. HYNDMAN, Chairman 

J. A. HAMMOND 

O. F. NEU 

W. H. OFFENHAUSER, JR. 

M. W. PALMER 



E. I. SPONABLE 
J. H. SPRAY 
R. O. STROCK 
H. E. WHITE 



Ladies Reception Committee 

MRS. D. E. HYNDMAN, Hostess 



MRS. H. GRIFFIN 

MRS. J. A. HAMMOND 

MRS. P. J. LARSEN 

MRS. O. F. NEU 

MRS. W. H. OFFENHAUSER, 

JR. 



MRS. P. D. RIES 
MRS. E. I. SPONABLE 
MRS. R. O. STROCK 
MRS. H. E. WHITE 
MRS. E. A. WILLIFORD 



Projection Committee 

H. F. HEIDEGGER, Chairman 



W. W. HENNESSY 
J. J. HOPKINS 
C. F. HORSTMAN 
L. B. ISAACS 
A. L. RAVEN 



F. H. RICHARDSON 

P. D. RIES 

J. E. ROBIN 

H. RUBIN 

R. O. WALKER 



Officers and Members of New York Projectionists Local No. 306 

HOTEL RESERVATIONS AND RATES 

Hotel Rates. The Hotel Pennsylvania extends to SMPE delegates and guests 
the following special per diem rates, European plan : 
Room with bath, one person $3 . 85-$7 . 70 

Room with bath, two persons, double bed $5. 50-$8. 80 

Room with bath, two persons, twin beds $6 . 60-$9 . 90 

Parlor suites : living room, bedroom, and bath $10 . 00, 1 1 . 00, 13 . 00, 

and 18. 00 

Reservations. Early in September room-reservation cards were mailed to the 
members of the Society. These cards should be returned to the hotel as promptly 
as possible to be assured of desirable accommodations. Reservations are subject 
to cancellation if it is later found impossible to attend the meeting. 

Registration. The registration headquarters will be located on the 18th floor 
of the Hotel at the entrance of the Salle Moderne, where most of the technical 



Oct., 1942] FALL MEETING 261 

sessions will be held. All members and guests attending the meeting are expected 
to register and receive their badges and identification cards required for admission 
to all sessions. 

TECHNICAL SESSIONS 

Technical sessions will be held as indicated on the next page. The Papers 
Committee is assembling an attractive program of technical papers and presen- 
tations, the details of which will be given in a Tentative Program to be mailed 
to the members of the Society about October 10th. 



FIFTY-SECOND SEMI-ANNUAL BANQUET AND INFORMAL GET-TOGETHER 

The usual Informal Get-Together Luncheon for members, their families, and 
guests will be held in the Roof Garden of the Hotel on Tuesday, October 27th, at 
12:30 P. M. 

The Fifty-Second Semi-Annual Banquet and dance will be held in the Georgian 
Room of the Hotel on Wednesday evening, October 28th, at 8:00 P. M. Pres- 
entation of the Progress Medal and Journal Award will be made at the banquet, 
and the officers-elect for 1943 will be introduced. The evening will conclude with 
dancing. 

LADIES' PROGRAM 

Mrs. D. E. Hyndman, Hostess, and members of her Committee promise an 
interesting program of entertainment for the ladies attending the meeting, the 
details of which will be announced later. A reception parlor will be provided for 
the Committee where all should register and receive their programs, badges, and 
identification cards. 

MISCELLANEOUS 

Motion Pictures. The identification cards issued at the time of registering will 
be honored at the Paramount Theater, the Roxy Theater, the Capitol Theater, 
and Radio City Music Hall. Many entertainment attractions are available in 
New York to out-of-town delegates and guests, information concerning which 
may be obtained at the Hotel information desk or at the registration head- 
quarters. 

Parking. Parking accommodations will be available to those motoring to the 
meeting at the Hotel garage, at the rate of $1.25 for 24 hours, and in the open lot at 
75 cents for day parking. These rates include car pick-up and delivery at the 
door of the Hotel. 

Golf. Arrangements may be made at the registration desk for golfing at 
several country clubs in the New York area. 

Note: The dates of the 1942 Fajl Meeting immediately precede those of the 
meeting of the Optical Society of America at the Hotel Pennsylvania, New 
York, N. Y., to be held on October 30th and 31st. 

The Convention is subject to cancellation if later deemed advisable in the na- 
tional interest. 



262 



FALL MEETING 



TENTATIVE PROGRAM 

Tuesday, Oct. 27 

9: 00 a.m. Hotel Roof; Registration. 

10:00 a.m. Salle Moderne; Business and Technical Session. 
12: 30 p.m. Roof Garden; SMPE Get-Together Luncheon for members, their 
families, and guests. Introduction of officers-elect for 1943 and 
addresses by prominent members of the motion picture industry 
2:00 p.m. Radio City Music Hall Studio; Technical Session. 
8:00 p.m. Museum of Modern Art Film Library; Technical Session. 

Wednesday, Oct. 28 

9 : 00 a.m. Hotel Roof; Registration. 

9: 30 a.m. Salle Moderne; Technical sessions. 

12:30 p.m. Luncheon Period. 

2: 00 p.m. Salle Moderne; Technical session. 

8 : 00 p.m. Georgian Room; Fifty-Second Semi- Annual Banquet and Dance. 

Thursday, Oct. 29 

9:00 a.m. Hotel Roof; Registration. 
10: 00 a.m. Salle Moderne; Technical Session. 
12:30 p.m. Luncheon Period. 
2 : 00 p.m. Salle Moderne; Technical Session. 
8:00 p.m. Salle Moderne; Technical Session and Convention adjournment. 

Note: Any changes in the location of the technical sessions and schedules of 
the meeting will be announced in later bulletins and in the final program. 

W. C. KUNZMANN, 
Convention Vice- President 



IMPORTANT 

Hotel room reservation cards must 
be returned immediately; otherwise 
the Hotel Pennsylvania can not guar- 
entee satisfactory accommodations on 
account of the recent large influx of 
visitors to New York. 



ABSTRACTS OF PAPERS 

FOR THE 
FIFTY-SECOND SEMI-ANNUAL MEETING 

HOTEL PENNSYLVANIA 

NEW YORK, N. Y. 
OCTOBER 27-29, 1942 

The Papers Committee submits for the consideration of the membership abstracts 
of papers to be presented at the Fall Meeting that have been received thus far. It is 
hoped that the publication of these abstracts will encourage attendance at the meeting 
and facilitate discussion. The papers presented at Meetings constitute the bulk of the 
material published in the Journal. The abstracts may therefore be used as convenient 
reference until the papers are published. 

A. C. DOWNES, Editorial Vice- President 

S. HARRIS, Chairman, Papers Committee 

C. R. SAWYER, Chairman, West Coast Papers Committee 

J. L. FORREST 

F. T. BOWDITCH C. R. KEITH W. H. OFPENHAUSER 

G. A. CHAMBERS E. W. KELLOGG R. R. SCOVILLE 
F. L. EICH P. J. LARSEN S. P. SOLOW 

R. E. FARNHAM G. E. MATTHEWS W. V. WOLFE 

Recent Laboratory Studies of Optical Reduction Printing; R. O. DREW AND 
L. T. SACHTLEBEN, RCA Manufacturing Co., Indianapolis, Ind. 

This paper reports recent laboratory work that has resulted in marked improve- 
ments over previous 16-mm reduction print quality. Improvements in image 
quality accrue from exposure of the print with ultraviolet light, and from the use 
of reflection-reducing coatings on the lens surfaces, while speed variations are re- 
duced by increasing printer speed to as much as twice the normal film speed. 
These improvements involve only relatively simple changes in commercial reduc- 
tion printers. 

Precision Recording Instrument for Measuring Film Width; S. C. CORONITI 
AND H. S. BALDWIN, Agfa Ansco, Binghamton, N. Y. 

The film passes through a film gauge, one member of which is fixed and the other 
movable. The latter is attached to one plate of an electrical condenser. Changes 
of film width are translated into changes of capacitance. The electrical condenser 
is connected to a parallel tuned circuit which acts as a load in the screen-grid cir- 
cuit of a crystal oscillator. A 1 dc milliammeter is connected in series with the 
screen grid. The circuit is tuned to some point off resonance. The dc screen- 
grid current corresponding to this point operation is balanced out. Therefore, 

m 



264 ABSTRACTS OF PAPERS [J. S. M. p. E. 

any changes of capacitance will vary the screen-grid current. For a width varia- 
tion of 0.250 mm the relationship between screen-grid current and film width is 
linear. 

A continuous recording milliammeter is connected in the meter circuit. Its 
chart velocity and film velocity are maintained at a fixed ratio. The accuracy of 
the instrument is 0.002 mm. 

Some Characteristics of Ammonium Thiosulfate Fixing Baths; DONALD B. 
ALNUTT, Mallinckrodt Chemical Works, St. Louis, Mo. 

A brief description of the history and nature of ammonium thiosulfate is given. 
Several practical formulas employing this agent are presented and their advan- 
tages discussed. Some of the differences in characteristics between the am- 
monium thiosulfate and sodium thiosulfate fixing baths are pointed out. 

An explanation is offered to account for the apparent discrepancies in the effects 
of concentration on clearing time reported by previous investigators. The speed 
of fixation of ammonium thiosulfate is shown to be greater than that of sodium or 
lithium thiosulfates and greater than that of mixtures of ammonium chloride 
and sodium thiosulfate. 

Motion Pictures in Aircraft Production; NORMAN MATHEWS, Bell Aircraft 
Corp., Buffalo, N. Y. 

The great numbers of aircraft needed in this war posed new problems in the 
training of maintenance personnel in sufficient numbers ; every plane in the air re- 
quires that there be three to twelve men on the ground for servicing. Each branch 
of our armed forces was faced with the big job of training many men rapidly, not 
only in the maintenance of aircraft, but in every phase of modern warfare. A 
great share of this training job could be done by means of motion pictures. 

Although the U. S. Army was producing an extensive series of training films 
dealing with aircraft maintenance, the Bell Aircraft Corporation believed that it, 
too, could help in this respect. Its service department had been in the field close 
to the problems of maintaining one particular type of aircraft and it was from 
their experience that material could be drawn for the production of training films 
dealing with servicing the P-39, the Army Airacobra. 

In April of this year the motion picture division of this company was organized 
and production was begun on an extensive series of films, each dealing with a 
specific service operation. All work was to be done in 16-mm and, with the ex- 
ception of the laboratory, all phases of motion picture production were handled in 
the division. Working closely with the service department, the details of the 
various operations were carefully checked for accuracy and instructional value. 
The small staff was organized into two crews, each alternating weekly in the 
writing and shooting of scripts. All phases of production on a number of films 
were kept moving simultaneously, with the added advantage from a working 
point of view of having one crew follow a picture through from the initial script 
stage to the final release. 

Aside from being used by the Army these films were to be used by the company's 
service department to train a rapidly expanding personnel and to help with serv- 
ice training in the field. Service representatives throughout districts in the 



<*t., 1^42] ABSTRACTS OF PAPERS 265 

various war-fronts were equipped with small sound projectors and complete sets 
of these films. A broader distribution was to be effected by the Army itself, 
which is placing these films in all bases where these planes are in service. 
The success of the films in aiding the training program is evidenced by their desig- 
nation as official Army training films, and further by the results of a question- 
naire aimed at an evaluation of them. 

Pilot training is another subject being treated in film to tie in with the Army's 
recently organized safety campaign. It is planned also that soon the work of the 
motion picture division will be expanded to include industrial training, for which 
there is an urgent need today in the aircraft industry with its rapid expansion 
and the introduction of new methods of fabrication. 



The Practical Side of Direct 16-Mm Laboratory Work; LLOYD THOMPSON, The 
Com puny, Kansas City, Mo. 

Laboratory practice for direct 16-mni production differs somewhat from 35- 
mm methods. Thirty-five-mm laboratory practice as we know it is largely 
confined to negative-positive, and 35-mm color is mostly done by special service 
laboratories and not by the studio or release print laboratories. 

Direct 16-mm production calls for the reversal type of processing, the negative- 
positive method, and color developing. Some producers own laboratories for 
doing the first two, but color is processed by the manufacturer. However, inde- 
pendent laboratories are printing color. It is the purpose of this paper to ex- 
plain how some of these processes are used in direct 16-mm production, especially 
when the methods differ from conventional 35-mm practices. Some of the sub- 
jects discussed are: processing originals, work prints, reversal printing, dupe 
negatives, color printing, control methods, special laboratory equipment, etc. 

Sixteen-Mm Editing and Photographic Embellishment; LARRY SHERWOOD, 
The Calvin Company, Kansas City, Mo. 

The paper will first discuss the essential equipment necessary to the editing of 
16-mm film, with a detailed analysis of the types of commercial equipment avail- 
able. Also will be included certain equipment that has been developed outside the 
commercial field. 

The second section will concern itself with the technique and methods that have 
been developed and proved to be applicable to the editing of 16-mm film. This sec- 
tion will take up the methods of identifying film ; of synchronization ; of matching 
work print with original, both sound and photography, without edge-numbering; 
and the technique of preparing film for the laboratory, with particular regard to the 
methods employed in laying in mattes to produce dissolves, doubU- r\postin-s, trick 
effects, etc. 

The third section will concern itself with the importance of trick effects in indus- 
trial and educational motion pictures; how trick effects might be utilized as an 
integral part of the educational process; and examples will be given to show how 
trick effects might be employed to eliminate footage, so essential to the produc- 
tion of this type of film. 



266 ABSTRACTS OF PAPERS [J. S. M. p. E. 

Carbon Arc Projection of 16-Mm Film; W. C. KALB, National Carbon Co., 
Cleveland, Ohio. 

This paper summarizes the characteristics of the high-intensity carbon arc as 
applied to the projection of 16-mm film. It includes a description of the carbon 
trim, color quality of the light, magnification, optical speed, and power require- 
ments of the projection lamp. Intensity and distribution of screen light are dis- 
cussed in relation to the operating characteristics of projectors commercially 
available and the transmission characteristics of heat filters, shutters, and avail- 
able types of lenses. Resulting screen illumination is interpreted in terms of 
screen dimensions and audience capacity under conditions conforming to recom- 
mended projection standards. 



Laboratory Practice in Direct 16-Mm Sound-Film Production; W. H. OFFEN- 
HAUSER, JR., Washington, D. C. 

In a paper such as this, it is not uncommon to find minute detail of machinery 
design and operation that is of little interest to any other than those who use the 
machinery or its product. If, however, a motion picture film laboratory is de- 
fined as but one of a series of tools necessary to accomplish the effective trans- 
mission of intelligence by means of the 16-mm sound motion picture as a com- 
munication medium, the laboratory takes on a new aspect that of function. 
It is with function that this paper deals, together with its inescapable results in 
machinery and machinery operation. 

Before our entry into the present World War, 16-mm films had been widely used 
for advertising and ballyhoo purposes ; advertising seemed best able to supply the 
largest sums for 16-mm production budgets. With our entry into the war, the 
voices that had cried in the wilderness a decade ago for instructional and training 
uses of film were finally heard; the death knell for the ballyhoo film occurred 
"for the duration," and training films marched in to displace and overrun them. 
This limitation of function was a blessing in disguise; the industry was per- 
mitted for the first time to clear decks of non-essential frills and strip for action. 

Direct 16-mm sound-films are generally of two kinds: black-and-white, and 
color (usually Kodachrome). In both cases the original picture is developed by 
the film manufacturer or his agents; the cost of development is included in the 
price paid for the film. 

The sound used is scored as a sound negative after the picture is edited; it is 
from this stage onward that the commercial laboratory enters. In the case of 
black-and-white, a fine-grain duplicate (intermediate) negative is made of the 
picture, release prints being made from the original sound negative and the inter- 
mediate picture negative. In Kodachrome, a black-and-white fine-grain positive 
print is made of the sound, the Kodachrome duplicates being made from the origi- 
nal Kodachrome picture and the black-and-white fine-grain sound-track print. 

The paper deals with procedures, and presents some of the highlights of equip- 
ment and operational techniques used in the volume production of high-quality 
copies. 



Oct.. 1942] ABSTRACTS OF PAPERS 267 

Film Distortions and Their Effect on Projection Quality; E. K. CARVER, R. H. 
TALBOT, AND H. A. LOOMIS, Eastman Kodak Co., Rochester, N. Y. 

The three main types of film distortion are (2) Embossing due to differential 
shrinkage or hardening of the emulsion caused by local absortion of heat in the 
dense portions of the picture; (2} Fluted edges due either to stretching of the 
edges or shrinkage of the center; (5) Short edges or buckle due to shrinkage of 
the edges while in the roll. 

Careful tests have failed to show any effect on the screen, such as in- and out- 
of-focus effects, due to image embossing. Measurements of the magnitude of the 
distortions show that these are ordinarily much less than the depth of focus of 
the lens. Laboratory tests as well as field experience indicate that fluted edges 
very rarely cause distortion of the image on the screen. 

Short edges, however, produce a type of buckle which often shows in- and out-of- 
focus effects. This is due to the fact that short edges leave a fullness in tin 
center similar to the bottom of an oil can. Under some circumstances (his 
fullness causes a movement back and forth in the projector gate causing in- and 
out-of-focus movement. Short edges are commonly caused by loss of moisture 
from the edges of the film when wound up in a roll immediately after processing. 
When such films are placed in tin cans, the rate of loss is reduced so that moisture- 
has time to diffuse from the center of the film to the edges and permit uniform 
shrinkage. A scarcity of tin and substitution of cardboard boxes makes it de- 
sirable to dry the film more thoroughly on the processing machines so as to avoid 
this quick loss of moisture during the storage period before projection. Trouble- 
can be avoided also by wrapping the film in moist ure-vaporproof envelopes before 
packing in cardboard boxes or by the use of cardboard boxes of a highly imperme- 
able type. 



Effect of High Gate Temperatures on 35-Mm Film Projection; E. K. CARVI- K. 
R. H. TALBOT, AND H. A. LOOMIS, Eastman Kodak Co., Rochester, N. Y. 

In a study of the effects of high temperature arcs on 35-mm motion pictim 
film in the projector gate, high-speed Cine Kodak pictures (1400-1500 frames per 
second) were taken of the image of the 35-mm film on the projection screen. In 
making these pictures an E-7 projector with a Macauley Hy-candescent lamp was 
used and the image was sharply focused on the projection screen. A portion of 
this image was used as a target for the high-speed Cine Kodak so that when this 
Cine Kodak picture was projected one could observe the appearance of the 35- 
mm image during various portions of each frame. The shutters of the 35-mm 
projector were thrown slightly out of synchronism so that the appearance of the 
image as it came to rest in the gate could be determined. When the high-speed 
16-mm pictures were projected, it was observed that the 35-mm image was in 
sharp focus during only a small part of its stay on the projection screen. After 
the pull-down, the film comes into the gate out of focus, and slowly moves into 
focus. As it moves into fdcus it always moves toward the lamp, as if the emulsion 
were expanding, thus causing the film to curl away from the emulsion. In some 
cases it does not come into sharp focus until after the flicker blade has passed. 
The above phenomena occur during all normal projections but are more prominent 



268 ABSTRACTS OF PAPERS [J. S. M .p. E. 

at higher temperatures. The 35-mm projected pictures appear to be perfectly 
sharp, even though the high-speed analysis shows them to be out of focus during 
a large fraction of their stay on the screen. If the image is in focus during the last 
fraction of a second before the next pull-down, it appears sharp to the eye regard- 
less of the fact that it was out of focus during the first part of its stay on the screen. 

Under certain definite circumstances, however, in- and out-of-focus effects are 
observed on the 35-mm screen. When these are observed, the high-speed movies 
indicate that the film comes into the gate out of focus, moves toward' the lamp 
and, therefore, toward sharp focus, but before it reaches sharp focus a sudden 
drift toward the lens occurs. Thus the film never reaches its position for sharp 
focus and gives the in- and out-of-focus effect. 

A further study of these effects was made by cutting away part of the projector 
gate so that a high-speed Cine Kodak can be focused directly onto the film in the 
gate. This study showed exactly the same effects as described above but, in some 
respects, made them clearer. 

The Use of High-Speed Photography in Analyzing Fast Action; E. M. WAT- 
SON, Capt. t Ordnance Dept., Watervliet Arsenal, Watervliet, N. Y. 

Various methods and devices may be used in studying action that is too fast for 
unaided visual observation. In almost every set-up the following points must be 
considered: (1) Means must be devised for placing the image (with necessary 
sharpness and steadiness) on the medium where the exposure is to take place; 
(2) Arrangements must be made for starting and stopping the exposure; (3) 
Means must be devised for placing the subsequent exposures on recording ma- 
terial at the proper time and location to obtain the desired results. 

The principal methods for studying high-speed action are the shutter method and 
the stroboscopic method. The former is used where subjects radiate light of them- 
selves or reflect utility light not used to determine exposure time ; exposure time is 
determined by the shutter. The stroboscope is used where other light does not 
materially interfere with stroboscopic light; exposure time is determined by the 
stroboscopic flash. 

Whenever the subject being investigated does not repeat its motion at all or not 
often enough to use a stroboscopic device, it is necessary to use some form of 
photography for quickly recording the action for later study ; when complications 
are not great, still cameras can be used. When a single picture is insufficient and 
the motion occupies approximately the same area, causing multiple images to 
overlap and be confused, one must resort to motion pictures. Motion pictures 
taken at speeds moderately in excess of the regular projection speed can be taken 
with an intermittent camera. When the film speeds up to about ninety miles per 
hour it is necessary to use some kind of device for placing the image on the film 
while the film is moving at a constant linear speed. If these additions are to be 
exceeded it is then necessary mechanically to support the film in motion or allow 
it to remain stationary and move the light which affects the exposure. 

In any kind of high-speed photography, all the limitations of ordinary photog- 
raphy are encountered plus some special restrictions imposed by the high speed. 
As types of cameras are changed to obtain increased speed, compromises in image 
quality and exposure must be made. 



Oct., 1942] ABSTRACTS OF PAPERS 

There is opportunity in high-speed photography for anyone having only modest 
equipment, but many of the applications require very expensive equipment which 
has little versatility. 

Effect of Composition of Processing Solutions on Removal of Silver from 
Photographic Materials; J. I. CRABTREE, G. T. EATON, AND L. E. MUKHLER, 
Eastman Kodak Co., Rochester, N. Y. 

To insure the permanence of the photographic negative or print it is necessary 
to remove all residual hypo and silver. The effect of composition of the processing 
solutions on hypo removal has been discussed in a previous paper. The factors 
which govern the removal of residual silver are considered in the present paper. 

The retention of silver in the photographic material gives rise to a yellowing of 
the non-image area of the negative or print under adverse storage condition^, t IK 
stain consisting of silver sulfide produced either by decomposition of complex 
silver thiosulfates or the action of hydrogen sulfide present in the atmosphere on 
the residual silver salts. 

Present practice of using a single fixing bath to exhaustion except in th<-i 
cases where the concentration of silver is kept at a minimum by electrolysis does 
not insure the complete removal of residual silver. With films the use of two 
fixing baths is necessary but with prints intended for archival purposes three 
fixing baths are required; preferably with a water rinse between baths. Two 
fixing baths are sufficient for the normal processing of prints. Data on the 
limiting concentrations of silver in the fixing baths and the photographic materials 
are given. 

The following factors affect the rate of removal of silver: (a) the pH of the 
fixing baths and the wash water, (b) the nature of the hardener employed in the 
fixing bath, and (c) the temperature of the wash water. Practical recommenda- 
tions are given for the removal of silver to produce photographic negatives and 
prints for (a) archival storage, and (b) normal keeping periods. 

Copper and Sulfide in Developers; R. M. EVANS, W. T. HANSON, JR., AND 
P. K. GLASOE, Eastman Kodak Co., Rochester, N. Y. 

The formation of excessive fog by a developer containing copper or sulfide is 
well known. However, no quantitative method for determining the concentration 
of either copper or sulfide in a developer appears to have been published. In t hi-* 
paper, polarographic methods of analysis for these substances are given together 
with photographic determinations of the effect of concentration on fog, thus 
demonstrating that the analyses are capable of determining the minimum amount 
of copper or sulfide required to cause fog under the conditions used. 

The fogging action of a developer which has accumulated sulfide by bacterial 
action is shown to be the same as that produced by a fresh developer containing 
the equivalent quantity of sodium sulfide. 

Factors Affecting the Accumulation of Iodide in Used Photographic Developers; 
R. M. EVANS, W. T. HANSON, JR., AND P. K. GLASOB, Eastman Kodak Co., 
Rochester, N. Y, 



270 ABSTRACTS OF PAPERS 

Development of uniformly flashed motion picture film has been carried out in 
developers of varying composition and the amount of iodide, which remains in the 
developer, determined by analysis. The amount of iodide in the developer was 
found to increase under the following conditions: 

(1) Development to a higher density. 

(2) Increasing the footage of film for a given volume of developer. 
(5) Increasing the time of development for the same density. 

(4) Increasing the strength of the developer. 

(5) Increasing the proportion of the surface covered by image. 

These results are explained by a kinetic equilibrium between the rate of release 
of iodide from the developing portion of the emulsion and the rate of removal 
of iodide from the developer by the undeveloped silver halide. 



BACK NUMBERS OF THE TRANSACTIONS AND JOURNALS 

Prior to January, 1930, the Transactions of the Society were published quar- 
terly. A limited number of these Transactions are still available and will be 
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portunity of acquiring these back numbers should do so quickly, as the supply 
will soon be exhausted, especially of the earlier numbers. It will be impossible 
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Beginning with the January, 1930, issue, the JOURNAL of the Society has been 
issued monthly, in two volumes per year, of six issues each. Back numbers of 
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$12.00. Single copies of the current issue may be obtained for $1.00 each. 
Orders for back numbers of Transactions and JOURNALS should be placed through 
the General Office of the Society and should be accompanied by check or money- 
order. 



SOCIETY SUPPLIES 

The following are available from the General Office of the Society, at the prices 
noted. Orders should be accompanied by remittances. 

Aims and Accomplishments. An index of the Transactions from October, 
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Journal Index. An index of the JOURNAL from January. 1930, to December, 
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Test- Films. See advertisement in this issue of the JOURNAL. 



S. M. P. E. TEST-FILMS 



These films have been prepared under the supervision of the Projection 
Practice Committee of the Society of Motion Picture Engineers, and are 
designed to be used in theaters, review rooms, exchanges, laboratories, 
factories, and the like for testing the performance of projectors. 

Only complete reels, as described below, are available (no short sections 
or single frequencies). The prices given include shipping charges to all 
points within the United States; shipping charges to other countries are 
additional. 



35-Mm. Visual Film 

Approximately 500 feet long, consisting of special targets with the aid 
of which travel-ghost, marginal and radial lens aberrations, definition, 
picture jump, and film weave may be detected and corrected. 

Price $37.50 each. 

16-Mm. Sound-Film 

Approximately 400 feet long, consisting of recordings of several speak- 
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ing sound optical system; fixed frequencies at constant level, for de- 
termining reproducer characteristics, frequency range, flutter, sound- 
track adjustment, 60- or 96-cycle modulation, etc. 

The recorded frequency range of the voice and music extends to 6000 
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6000 cps. 

Price $25.00 each. 

16-Mm. Visual Film 

An optical reduction of the 35-mm. visual test-film, identical as to 
contents and approximately 225 feet long. 
Price $25.00 each. 



SOCIETY OF MOTION PICTURE ENGINEERS 

HOTEL PENNSYLVANIA 

NEW YORK, N. Y. 



JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

VOLUME XXXIX NOVEMBER, 1942 

CONTENTS 

PAGE 
Re-Recording Sound Motion Pictures 

L. T. GOLDSMITH 277 

The Cutting and Editing of Motion Picutres 

F. Y. Smith 284 

Progress in the Motion Picture Industry: Report of 
the Progress Committee for 1940-11 294 

The Photographing of 16-Mm Kodachrome Short Sub- 
jects for Major Studio Release L. W. O'Connell 314 

Elimination of Relative Spectral Energy Distortion in 
Electronic Compressors B. F. MILLER 317 

Current Literature 324 

Society Announcements 327 

(The Society is not responsible for statements oj authors.) 



JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

SYLVAN HARRIS, EDITOR 

Board of Editors 

ARTHUR C. DOWSES, Chairman 

JOHN I. CRABTREE ALFRED N. GOLDSMITH EDWARD W. KELLOGG 

CLYDE R. KEITH ALAN M. GUNDELFINGER CARLETON R. SAWYER 

ARTHUR C. HARDY 

Officers of the Society 

*President: EMERY HUSE, 

6706 Santa Monica Blvd., Hollywood, Calif. 
* Past-President: E. ALLAN WILLIFORD, 

30 E. 42nd St., New York, N. Y. 
*Executive Vice-P resident: HERBERT GRIFFIN, 

90 Gold St., New York, N. Y. 
^Engineering Vice-President: DONALD E. HYNDMAN, 

350 Madison Ave., New York, N. Y. 
*Editorial Vice-President: ARTHUR C. DOWNES, 

Box 6087, Cleveland, Ohio. 
** Financial Vice-President: ARTHUR S. DICKINSON, 

28 W. 44th St., New York, N. Y. 

* Convention Vice-President: WILLIAM C. KUNZMANN, 

Box 6087, Cleveland, Ohio. 

* Secretary: PAUL J. LARSEN, 

1401 Sheridan St., N. W., Washington, D. C. 
^Treasurer: GEORGE FRIEDL, JR., 
90 Gold St., New York, N. Y. 

Governors 

*MAX C. BATSEL, 501 N. LaSalle St., Indianapolis, Ind. 
**FRANK E. CARLSON, Nela Park, Cleveland, Ohio. 

*JOHN G. FRAYNE, 6601 Romaine St., Hollywood, Calif. 

*ALFRED N. GOLDSMITH, 580 Fifth Ave., New York, N. Y. 
**EDWARD M. HONAN, 6601 Romaine St., Hollywood, Calif. 

*I. JACOBSEN, 177 N. State St., Chicago, 111. 
**JOHN A. MAURER, 117 E. 24th St., New York, N. Y. 

*LOREN L. RYDER, 5451 Marathon St., Hollywood, Calif. 

* Term expires December 31, 1942. 
** Term expires December 31, 1943. 



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Picture Engineers, Inc. 



RE-RECORDING SOUND MOTION PICTURES' 
L. T. GOLDSMITH** 



Summary. The nature of re-recording as it applies to motion picture production 
is described in some detail by showing what happens to a typical picture in the re- 
recording department after shooting on the set has been completed and the picture has 
been edited to the satisfaction of the producer. 

Sound is added to those portions of the picture that have been photographed silent 
because of the difficulty or impossibility of recording the corresponding sound at that 
time, as for example, credit titles, montages, miniatures, stock shots, and scenes photo- 
graphed silent to playbacks of pre-recorded sound. Music that has been especially 
scored and recorded for the picture together with appropriate sound-effects is added 
to heighten its dramatic presentation. 

Improvements in dialog quality are made if required by employing electrical equal- 
izers, although distortion is often purposely introduced where telephone, dictaphone, 
radio, and similar types of quality must be simulated as required by the picture. 

Proper balance of the relative volume of the dialog and accompanying music and 
sound-effects is determined to the satisfaction of the re-recording supervisor. All 
the sounds from as many as a dozen or more different sources are re-recorded to a 
single composite sound-track which is afterward printed with the picture to make up 
the final print to be projected in the theater. 

The organization of the re-recording department is discussed and the duties of vari- 
ous members of the personnel are outlined. Crews are so made up that an average of 
from three to six pictures are in work at the same time. 

A division of the sound department of every major film-producing 
studio is known as the re-recording department, sometimes called the 
dupe or dubbing department. In the days before sound pictures it 
was common practice in the laboratory, to make duplicate picture 
prints or "dupes," as they were called. Also, the special picture- 
effects department would often add foregrounds or backgrounds to a 
picture, a process termed "dubbing in" or "dubbing." So, in 
general, the duplicating process, with the finishing touches added, 
became known as duping or dubbing. 

The sound-duplicating process, especially since it is not photo- 
graphic but electrical duplicating, is more properly known as re- 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received May 
10, 1942. 

** Warner Bros. Pictures, Inc., Burbank, Calif. 

277 



278 L. T. GOLDSMITH [J. S. M. P. E. 

recording. As the name implies, sound originally recorded on film 
in synchronism with the picture being shot on the set, is recorded 
again from that film along with added sound-effects and music 
recordings to a second film. This film is a composite of all the 
desired sounds required for the picture. The composite sound-track 
is then printed on the same film as the corresponding picture and 
projected in the theaters. 

Suppose we take a typical picture as an example, and follow its 
progress through the re-recording department. After the shooting of 
the picture on the set has been finished, the picture editor assembles 
the daily prints of picture and sound : track in proper timing and 
continuity. These two prints are known as the cutting picture and 
cutting track. The producer who is responsible for this particular 
production runs the picture in this form with the editor, and indicates 
what changes he wishes made. When the picture is complete and 
the corresponding original dialog sound-track is approved, the editor 
delivers the picture to the re-recording supervisor. 

The film is received as separate picture and sound-track reels, 
which are close to 1000 feet long. The sound-track consists almost 
entirely of dialog and any sound-effects that may have happened to 
be recorded at the same time. The supervisor assigns the picture 
to one of the re-recording crews who check it reel by reel. 

The re-recording crew usually is made up of a re-recording mixer 
who acts as the crew chief, two sound-track editors who edit the 
music and further edit the dialog track, a sound-effects editor who 
prepares appropriate sound-effects for the picture, and a projectionist. 
The sound-track editors usually split up the reels between them, each 
man taking every other reel. They check the reels for synchronism 
and for words of the dialog that may have been cut off because of 
picture cuts. These will require an overlapping of two sound-tracks 
in re-recording. 

As the reels are run one by one, the sound-effects editor makes 
notes as to what kinds of sound-effects are required and where they 
should go into the picture. Some sound-effects are recorded es- 
pecially for the scene at the time the picture is shot. When such 
effects are made, the production mixer sends a memorandum to the 
re-recording department identifying by scene and take number, the 
effects that have been recorded and noting where in the picture they 
are to be used. 

The sound-track editors then run the sound-track and picture in 



Nov., 1942] RE-RECORDING SOUND PICTURES 279 

a moviola and make notes in ink on the sound-track film, indicating 
for the laboratory negative cutters which scenes are to be extended, 
and what scenes and effects are to be removed. Additional prints 
of the required scenes are ordered from the laboratory, which are 
assembled into a secondary dialog track to allow some of the dialog 
sentences to overlap when it is re-recorded. At the same time, the 
sound -effects editor orders the required number of sound-effects 
prints from the laboratory, both those made at the time the picture 
was shot and those made from sound-effects negatives kept in the 
sound-effects library. 

The picture and sound-track are then sent to the laboratory, where 
two composite sound-and-picture dupe prints are made. One of 
these dupe prints is sent to the music department, where it is used 
for checking the picture to determine where music must be scored. 
The other dupe print is sent to the re-recording department. The 
laboratory then cuts the original sound-track negative in accordance 
with the edge-numbers and inked instructions on the cutting sound- 
track, and makes a print. This may be called a primary dialog 
print, and is the print used in the re-recording. It is necessary to 
re-record from this new primary dialog track rather than from the 
original cutting track because in the new track certain dialog se- 
quences have been extended or removed at the laboratory to take 
care of overlaps. Furthermore, the original track has become 
scratched from the many runnings in the picture editor's moviola, 
and the new track has been blooped at all splices. When the labo- 
ratory delivers to the re-recording department the new primary 
dialog track, the additional prints of portions of the dialog, the prints 
of sound-effects, the composite dupe print, and the original picture 
and sound-track prints, the sound-editors begin to prepare the reels 
for re-recording. 

The sound-track editors, using the original cutting picture and 
cutting track as guides, prepare the secondary dialog track which 
will cover the overlaps in conjunction with the primary dialog track. 
At the same time, the sound-effects editor, using the dupe-picture 
print as a guide, cuts his sound-effects prints into reels to match the 
picture action. He may have the sound-effects on several reels 
because often more than one effect is required at one time. In 
addition, there are usually several loops of sound-effects which run 
all the time during the re-recording of the reel and can be mixed in 
as required. The loops are numbered and catalogued and consist 



280 L. T. GOLDSMITH [J. S. M. p. E. 

of the more frequently used sound-effects such as laughter, applause, 
crowd noise, street noise, etc. 

If the music recordings or "takes" are now available, the sound- 
track editor prepares the music tracks for re-recording, using the 
cutting-picture as a guide and following the footage notes prepared 
for him by the music department as to what the music selections are 
and where they go into the reel. Several music tracks are often 
required, and here again additional prints may have to be ordered to 
take care of overlaps in the music. As soon as a reel has been pre- 
pared either with or without all the music and effects tracks, it is run 
once to check for synchronism, overlaps, effects, etc. If no music 
has been received for that particular reel, the sound-track editors 
then set it aside and prepare another reel. 

The sound-track editors prepare a cue sheet for the re-recording 
mixer to use during the re-recording of each reel to indicate to him 
where the secondary dialog and music tracks come in and go out. 
A similar cue sheet is prepared by the sound-effects editor for his 
own use when he assists the mixer in re-recording the reel. These cue 
sheets must be corrected as changes are made during re-recording 
rehearsals, so that after the re-recording is made and the sheets are 
filed, they will be accurate if at some later time they are used again. 

When all the tracks are prepared, the re-recording mixer and the 
sound-effects editor, acting as an assistant mixer, proceed to rehearse 
the reel for re-recording. The mixer usually handles the dialog and 
music, and the assistant mixer handles the effects tracks. All the 
tracks, usually eight to twelve in number, are threaded on re-recording 
machines by machine-room attendants, and the speech circuits 
patched to the desired mixer controls on the mixer console. The 
projectionist who has the cutting or dupe picture to project on the 
screen as a guide to the mixer threads his print on a silent projector. 
In addition to the picture screen for watching the action, the mixers 
have an illuminated footage indicator similar to a veedor counter, 
which is used with the picture for cueing the various sound-tracks. 
A peak-reading neon volume indicator and theater-type loud speaker 
behind the screen serve as guides to the mixers as to the volume and 
balance of the dialog, music, and sound-effects tracks. 

After a number of rehearsals, depending upon the complexity of 
the reel, the re-recording supervisor is asked to approve a rehearsal. 
If he approves, a recording or "take" is made of the combined tracks 
on a film-recording machine. The film is sent to the laboratory as 



Nov., 1942] RE-RECORDING SOUND PICTURES 281 

the re-recording crew proceeds to the next reel. (It might be men- 
tioned here that a picture is not always re-recorded reel by reel con- 
secutively, because some reels may take longer to prepare for duping 
than others.) 

The following morning a checking print made from the sound 
negative is delivered by the laboratory to the sound department. 
This is run by the sound director in a review room with the cutting 
picture. It is carefully checked for synchronism, volume, quality, 
balance of sounds, and quietness. If the re-recording is judged 
faulty in some respect, the entire reel or part of it is ordered re- 
recorded again. Usually the reel is satisfactory and the laboratory 
is notified that a composite picture and sound print of it can now be 
made. The laboratory first cuts the original picture negative in 
accordance with the cutting picture print edge-numbers, and then 
makes the composite print from this and the re-recorded sound 
negative. When all the reels have been re-recorded and a com- 
posite print made of each, the picture is previewed in a neighboring 
theater. 

If there are changes to be made after the preview, the picture 
editor makes the required changes in the cutting picture and sound- 
track, and again delivers the affected reels to the re-recording depart- 
ment. Sometimes the changes are such that the previously re- 
recorded sound-track negative need only be cut to match the picture 
cut, but more often a re-recording has to be made of the sections 
affected, usually one or more small sections of reels, sometimes entire 
reels. A checking print of the new sections or reels is approved by 
the sound director, and the picture is either previewed a second tum- 
or is approved for making composite release prints. 

In the meantime, the re-recording crew has usually received another 
picture and begun its preparation for re-recording in the same way. 
The re-recording department has several such crews so that a number 
of pictures can be in various stages of re-recording at any one time. 

In addition to the re-recording crews that work directly on the 
picture there are the machine-room personnel who thread up the 
re-recording machines, and a man who is responsible for the recording 
and operation of the recording machines. Often several machine- 
room men and a single recordist are sufficient to handle the equip- 
ment for three or four re-recording crews. A transmission engineer, 
or maintenance man who sometimes is also the recordist, maintains 
all the electrical equipment. The mechanical equipment is usually 



282 L. T. GOLDSMITH [j. s. M. p. E. 

maintained by men who care for the rest of the equipment in the 
sound department as well. A representative of the music department 
is often assigned permanently to the re-recording department who is 
responsible for the music cutting, and acts as contact between the two 
departments. A film clerk receives all incoming and outgoing film 
and acts as general secretary to the department. 

In connection with the re-recording of a picture the re-recording 
department is called upon for a variety of duties other than those 
mentioned. Pre-recordings may be required for timing the photo- 
graphed action on the set to a previously recorded song or dance 
number. Frequently the music recording for this has been made in 
sections. Perhaps a separate choir track of voices, an orchestra 
track, or even added tracks of trumpets, drum beats, or other effects 
may be needed. To permit the chorus and dancers to perform in 
proper tempo while they are being photographed without sound, a 
composite sound-track is played back to them on the set through 
loud speakers for timing. This track is made in the re-recording 
department by editing the various music tracks or parts of tracks, 
and re-recording them to the playback film or disk. 

Timing or "tick" disks are similarly prepared for the use of the 
orchestra in music scoring. The ticks are made in a special machine 
and so spaced that when played back to the members of the orchestra 
through headphones the musicians will be in tempo with each other 
and with the action of the picture. 

The re-recording department is equipped to record acetate disks 
at either 33 l /s or 78 rpm, as in some cases songs and musical numbers 
are re-recorded from film to disk for talent rehearsals at home or for 
music-publisher auditions. Microphone pick-up facilities are avail- 
able for recording sound-effects and wild lines of dialog. These can 
be timed by watching the picture on a screen or by following the 
dialog played back through headphones. 

Many kinds of circuit equalizers are used to distort the quality 
of speech or music purposely to simulate radio, telephone, dictophone, 
or other types of sounds. An "echo chamber" is available to simu- 
late voice sounds in large halls, caves, etc., and to add reverberation 
and life to some kinds of music. Sound-tracks are often run at 
variable speeds to achieve special effects, particularly in cartoons. 

No description has been given of the actual equipment, both 
electrical and mechanical, that is used in re-recording. There are 
many kinds of machines used for special purposes, and an adequate 



Nov., 1942] RE-RECORDING SOUND PICTURES 283 

description of them would cover many pages. For this reason, the 
reader is referred to the following bibliography, which lists publica- 
tions describing the equipment. 

BIBLIOGRAPHY 

LOOTENS, C. L., BLOOMBERG, D. J., AND RETTINGER, M.: "A Motion Picture 
Dubbing and Scoring Stage," J. Soc. Mot. Pict. Eng., XXXII (April, 1939), p. 357. 

MORGAN, K. F., AND LOVE, D. P.: "Sound Picture Recording and Reproducing 
Characteristics," /. Soc. Mot. Pict. Eng., XXXIII (July, 1939), p. 107. 

REISKIND, H. I.: "A Single-Channel Recording and Re-Recording System," 
J. Soc. Mot. Pict. Eng., XXVIII (May, 1937), p. 498. 

LOYE, D. P.: "Acoustic Design Features of Studio Stages, Monitor Rooms, 
and Review Rooms," /. Soc. Mot. Pict. Eng., XXXVI (June, 1941), p. 593. 

MUELLER, W. A.: "Audience Noise as a Limitation to the Permissible Volume 
Range of Dialog in Sound Motion Pictures," /. Soc. Mot. Pict. Eng., XXXV (July, 
1940), p. 48. 

AALBERG, J. O., AND STEWART, J. G. : "Applications of Non-Linear Volume Char- 
acteristics to Dialog Recording," /. Soc. Mot. Pict. Eng., XXXI (Sept., 1938), p. 
248. 

MUELLER, W. A.: "A Device for Automatically Controlling the Balance be- 
tween Recorded Sounds," /. Soc. Mot. Pict. Eng., XXV (July, 1935), p. 79. 

CRANE, G. R. : "Variable Matte Control (Squeeze-Track) for Variable- Density 
Recording," /. Soc. Mot. Pict. Eng., XXXI (Nov., 1938), p. 531. 

HOPPER, F. L. : "Electrical Networks for Sound Recording," /. Soc. Mot. Pict. 
Eng., XXXI (Nov., 1938), p. 443. 

"How Motion Pictures Are Made," /. Soc. Mot. Pict. Eng., XXIX (Oct., 1937). 
p. 349. 

KIMBALL, H. R. : "Application of Electrical Networks to Sound Recording and 
Reproducing," /. Soc. Mot. Pict. Eng., XXXI (Oct., 1938), p. 358. 

WILLIAMS, F. D.: "Methods of Blooping," /. Soc. Mot. Pict. Eng., XXX (Jan., 
1938), p. 105. 

OFFENHAUSER, W. H., JR.: "Current Practices in Blooping Sound-Film," /. 
Soc. Mot. Pict. Eng., XXXV (Aug., 1940), p. 165. 

STROCK, R. O.: "Some Practical Accessories for Motion Picture Recording," 
J. Soc. Mot. Pict. Eng., XXXII (Feb., 1939), p. 188. 

LAMBERT, K. B.: "An Improved Mixer Potentiometer," J. Soc. Mot. Pict. 
Eng., XXXVII (Sept., 1941), p. 283. 

READ, S., JR: "A Neon-Type Volume Indicator," /. Soc. Mot. Pict. Eng., 
XXVIII (June, 1937), p. 633. 



THE CUTTING AND EDITING OF MOTION PICTURES* 

FREDRICK Y. SMITH** 

The Physical Aspect 

Summary. The first part of this paper deals with the physical aspect of cutting 
and editing motion pictures that is, the manner in which the film is physically 
handled in the process of assembling the various "dailies," "rushes," and other forms 
of film up to the time of release. 

The second part of the paper deals with the editorial aspect that is, the assembling 
of the various shots of the picture and the importance of the proper arrangement of 
these shots in producing the desired dramatic effects. 

Questions usually asked by visitors to a studio Cutting Room are, 
"What is a film editor?" "What does he do?" "Is a cutter a film 
editor?" In fact, questions like these are asked not only by laymen, 
but also quite often by workers of other crafts in the industry. No 
one thinks of asking, "What is a director, a cameraman, or a writer?" 
Their professions were known before motion pictures existed. There- 
fore, it seems to follow that whatever the skills and artistic accom- 
plishments of the film editor or cutter they are specific for this 
medium of expression, and have grown out of motion pictures. 

Webster's New International Dictionary gives the following de- 
finitions : 

Cutter: One who cuts ; as a stone cutter ; specif. : (1) one who cuts out garments ; 
(2) one whose work it is to cut a (specified) thing (in a specified way), as in: 
amethyst cutter, machine cutter, disc cutter, gravestone cutter, timber cutter, film cutter. 

Editor: One who produces or exhibits. One who prepares the work of another 
for publication ; one who revises, corrects, arranges, or annotates a text, document, 
or book. 

Substituting the word exhibition for publication, and film for text, 
document, or book, we have a fairly simple yet accurate definition of a 
Film Editor. 

This title appearing on the technical credit card of most motion pic- 
tures produced today refers to the person who assembles the scenes 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received May 
30, 1942. 

** Metro-Goldwyn-Mayer Studios, Culver City, Calif; President, Society of 
Motion Picture Film Editors, 1941-42. 
284 



CUTTING AND EDITING PICTURES 285 

after they are photographed and who is invariably referred to in the 
industry as the cutter. Whereas the term film editor is more indica- 
tive of the creative nature of the work, the term cutter seems to imply 
that the process is the work of a technician who performs his duties 
according to the standards and regulations of this profession. 

This creator-technician position, as we know it now, was a child of 
necessity. Mass production of motion pictures demanded a person 
who would keep the film assembled so that when the last scenes of the 
picture were photographed the producer could expect an early projec- 
tion of the final total results. 

With the advent of sound, film cutting became a much more in- 
volved process than it was in the era of silent pictures. In those days 
it may have been possible to edit a picture with a work-bench, a set 
of rewinds, a pair of scissors, film cement, a viewing device, and a 
receptacle for the film. 

Since the introduction of sound, film cutting has become much more 
technical; and before considering the artistic phase of editing, we 
must first become acquainted with the mechanical side of the business. 
This necessitates a description of the materials with which the editor 
works, the tools at his disposal, and the application of these tools to 
the materials at hand. The tools of the cutting room consist of 
reels, rewinds, flanges, synchronizers, scissors, film cans, bins, racks, a 
splicing machine and a viewing machine (moviola) . 

When the positive film comes from the laboratory to the cutting 
room, the first operation, unless it has been done already in the lab- 
oratory, is the synchronizing of the "rushes," or "dailies," which are 
the terms given to the scenes taken by a producing unit the previous 
day. A set of synchronizing leaders is prepared, and attached 
to the right-hand rewind apparatus. Identification marks are placed 
on these "sync" leaders, giving the number of the reel and stating 
whether it is picture or sound-track. These sync leaders are 16 feet 
long, the first four feet being required for threading the projector, 
and the next 12 feet being necessary to permit the projector to get up 
to full speed before showing the picture on the screen and reproducing 
the sound. Four feet from the beginning of each leader a frame is 
marked off on both picture and sound-track for the "starting mark." 
The frames thus marked are placed directly opposite each other on 
the wheels of the synchronizer and locked in position. The cutter 
then now winds through the remaining 12 feet of leader, and marks 
off both pieces on the frame line of the synchronizer. 



286 F. Y. SMITH [j. s. M. P. E. 

The closing of the "clappers" on the picture film and the sharp 
modulations on the sound-track recording the noise of the clappers 
provide the synchronizing cue. The picture reel is unrolled to the 
point of the first scene, where the synchronizing clappers are seen to 
come together, and the frame is marked. The point of the correspond- 
ing modulation on the sound-track film is also marked, and the two 
films are then placed in synchronism on the synchronizer and wound 
back to the start of the scene, where the films are cut. They are then 
fastened, by means of paper clips, to the leaders and wound on to their 
respective reels. The markings are made on the emulsion side of the 
film with red grease pencil, which can be easily wiped off with a clean, 
dry cloth without damaging the film. The use of carbon tetrachloride 
will greatly help the cleaning. 

Sometimes the clapper marks occur at the end of the scene, usually 
under the following circumstances : 

(1) When the position of the camera on the opening shot is such that it would 
be inconvenient to use the clappers. 

(2} When it is necessary to avoid frightening the subject or impairing his acting 
ability by any sudden shock or noise (e.g., an infant, or an animal). 

The synchronizing of scenes when the clappers occur at the end is 
accomplished in the same way as described before. The clapper 
marks are framed ; a foot of identifying slate footage is retained after 
the marked frame; and then the scene is wound back to the begin- 
ning of the scene and cut at the light flash. Where an interlocked 
start is used, or a synchronized fog mark is made, the procedure is the 
same, the fog marks being substituted for the clapper marks. 

When all the scenes of one day's shooting have been thus syn- 
chronized and all the splices have been made, the "dailies" are pro- 
jected for the approval of the producer, director, cameraman, and 
editor, after which they are sent to the numbering room. Here the 
film is put through a numbering machine similar to the machine that 
prints the key numbers on the negative. The sound-track and pic- 
ture films are threaded on machines so that the number 000 will be 
printed at the "start" marks and every foot of film is thereafter num- 
bered consecutively. The numbers are printed along the clear edge 
of the film on the side opposite the negative key numbers. 

After the film has been numbered it is delivered to the continuity 
room where typists make up the continuity sheets giving scene number, 
description of angle and action, and the exact dialog. From the con- 



Nov., 1942] CUTTING AND EDITING PICTURES 287 

tinuity department the "dailies" are returned to the cutting room, 
where the first and last negative key numbers of each scene, both pic- 
ture and track, are written on cards which are later filed in index form. 
This procedure enables the assistant editor promptly to locate the 
trims of scenes after they are cut and filed away. 

The "dailies" are now ready to be broken down. This process is 
accomplished with the aid of a disk or flange. The disk is placed on 
the rewind to the right of the operator, while the reel of action or sound 
to be broken down is placed on the left rewind. A ground-glass plate 
lighted from below is between the rewinds, so that the film may be 
viewed easily. The film is broken at the end of the scene, and the 
roll of film that has been wound upon the disk is removed from the 
spindle. 

The film is now ready for cutting by the film editor, or it may be 
filed away in tins, marked with the scene number in racks or in lock- 
ers until such time as a sequence is completed and ready for a first 
assembly. 

Omitting the editorial functions, we come to the final mechanical 
stages of cutting, which include the preparation and synchronization 
of music and additional sound-effects. These multiple sound-tracks 
consist of off -scene dialog, dictaphone dialog, echo or reverberant 
dialog, etc., sounds of water lapping on a shore, croaking of frogs, 
chirping of crickets, motorboat sounds, etc. These must all be in 
synchronism with the picture, and built for the purpose of "dubbing" 
or re-recording. The splices in the sound-track are painted over 
with photoblack or covered with scotch tape in the form of triangles 
or crescents, to eliminate the noise that would otherwise occur when 
the sound-track is reproduced in the theater. 

When the picture has been finally re-recorded and is ready for 
negative cutting, it is necessary for the Editor, or his assistant, to 
make a final check of the film, attach new standard leaders, fill in the 
picture with black frames and mark all negative jump-cuts unless 
specifically desired, and check the synchronizing numbers of each 
scene to the sprocket-hole code number opposite code number. All 
cuts not clearly obvious to the negative cutters are plainly marked, 
either by pen and ink, or by scratching the film with a stylus. 

This, in brief, constitutes the physical handling of film, but obvi- 
ously has omitted the creative aspect of the film editing. 



288 F. Y. SMITH [J. S. M. P. E. 

The Editorial Aspect 

Paul Rotha says, in part, "From the first days of film production 
until the present, most story -film technique to have emanated from 
Western studios has been based upon the fact that the camera could 
reproduce phenomena photographically onto sensitized celluloid, 
and that from the resulting negative a print could be taken and 
thrown in enlarged size by a projector onto a screen. In consequence, 
we find that more consideration is accorded the actors, scenery, and 
plot than the method by which they are given screen presence, a sys- 
tem of manufacture that admirably suits the departmental organiza- 
tion of the modern film studio. Thus the products of the scenario, 
together with the accommodating movements of the camera and 
microphone, are numerous lengths of celluloid, which merely require 
trimming and joining in correct sequence, according to the original 
scenario, for the result to be something in the nature of a film. Occa- 
sionally, where words and sounds fail to give the required lapses of 
time and changes of scene, ingenious camera and sound devices are 
introduced. It is not, of course, quite so simple as this but, in essen- 
tials, the completed film is believed to assume life and breath and 
meaning by the transference of acting to the screen and words to the 
loud speaker. 

"The skill of the artist, therefore, lies in the treatment of the story, 
the guidance of the actors in speech and gesture, the composition of 
the separate scenes within the picture-frame, movements of the 
cameras, and the suitability of the settings ; in all of which he is as- 
sisted by dialog- writers, cameramen, art-directors, make-up experts, 
sound-recordists, and the actors themselves, while the finished scenes 
are assembled in their correct order by the editing department. 

"Within these limits, the story-film has followed closely in the 
theatrical tradition for its subject-matter; converting, as time went 
on, stage forms into film forms, and stage acting into film acting, ac- 
cording to the exacting demands of the reproducing camera and micro- 
phone. 

"The opposite group of thought, however, while accepting the 
same elementary functions of the camera, microphone, and projector, 
proceeds from the belief that nothing photographed, or recorded on 
celluloid has meaning until it comes to the cutting bench; that the 
primary task of film creation lies in the physical and mental stimuli 
that can be produced by the factor of editing. The way in which the 
camera is used, its many movements and angles of vision in relation 



Nov., 1942] CUTTING AND EDITING PICTURES 289 

to the objects being photographed, the speed with which it repro- 
duces actions, and the very appearance of persons and things before 
it are governed by the manner in which the editing is fulfilled." 

To understand these words fully, let us go back to the beginning 
of the motion picture. Edwin S. Porter was working for the Edison 
Company in 1896 when that concern imported some pictures made 
by George Melies, a Frenchman. Porter studied these pictures very 
carefully and became aware of the tremendous effect such simple 
pictures had upon audiences. As a result an idea came to Porter 
that contained all the elements of motion picture making as we know 
it today, an idea that created a new art-form, a new mode of expres- 
sion, working with new tools. It was the first process of using me- 
chanical means to create emotional values. The idea was to try to 
tell a story with the new film medium by combining several shots or 
scenes in successive order, the story to be told not only through the 
action in a given scene, but also by the relation of that scene to the 
preceding and the following scenes, thus giving a coherent meaning to 
the whole. 

Porter's first motion picture telling a story was The Life of an 
American Fireman. He found some stock material about fires and fire 
brigades and then staged such additional scenes as his plot demanded. 
These scenes, together with the stock shots, he assembled into a 
dramatic continuity that has become the pattern for all motion pic- 
ture action stories since. 

The very same method which Porter used in his The Life of an 
American Fireman is frequently used today. It is not uncommon for 
a studio having a good deal of stock material of some exciting event to 
assign a producer, writer, and film editor to build a story around this 
material. This pertains particularly to the cheaper action pictures. 
A picture was released last year that contained about 3000 feet of 
stock scenes, and the entire length was only 7200 feet. 

Exactly what did Porter achieve? He discovered that real oc- 
currences can be made dramatic by means of editing, that the art of 
the motion picture depends not upon the shots alone, but upon the 
continuity of shots. He discovered that the combination of shots 
into scenes gives a meaning that is not in the individual shots; and 
that a scene need not be taken in one shot. A long period of time in 
actual life can be shown on the screen in a short period of time, and 
vice versa. 

The Life of an American Fireman contained a very significant in- 



290 F. Y. SMITH tf. S. M. P. E. 

novation, namely, the close-up. The second scene of the picture is a 
close-up of a New York fire-alarm box. This was at least five years 
before D. W. Griffith established the close-up as an integral part of 
motion picture technique. Porter discovered that a film story can be 
made from the sum of a number of individual scenes, but D. W. 
Griffith developed the new technique and applied it not only to story, 
but also to sequence, scene, and individual shot. He found that 
editing enables the dramatization of the moment, that it gives per- 
spective and interpretation. He became aware of the fact that mood 
and tempo could be created by the proper arrangement of scenes. 
He found a new technique by composing his scenes with a number of 
shots, each shot and scene being kept on the screen only long enough 
to portray the essential piece of business in its dramatic height. 
Without waiting for the end of a scene, he cut to the next, thus giving 
the whole a continuous flow and rhythm. The result, to quote from 
Lewis Jacobs, is that, "Not connected by time, separated in space, 
shots are now unified if affected by the theme. The basis of film 
expression has become editing, the unit of editing the shot and not 
the scene." 

Thus the invention of editing had a great effect upon story con- 
tent. The world was open, the sky the limit. Events of the moment 
could be put into relation to the dim past. The hero of the drama 
could travel to China and to the North Pole. New themes rapidly 
found their way onto the screen. 

In The Thread of Destiny Griffith found another use for shots. For 
the first time he shot scenes not called for in the script, scenes with- 
out action, to give atmosphere and background, thus underlining the 
narrative and action of the story and establishing mood and motive. 
He introduced the extreme long shot, giving the feeling of wide space 
and, when the story required it, he cut to an extreme close-up, achiev- 
ing a singular dramatic effect by the contrast. 

In the final analysis, motion pictures are movement. Story, drama, 
moods, and thoughts are expressed in movement. The action is 
movement, the camera moves. Cutting is movement, forcing the 
eye of the spectator to move from one scene, one object, from one 
angle to another. In cutting shorter and shorter, trimming the in- 
dividual shots down to the last of one essential fact, the rhythm of 
the movement is accelerated and the tension is led to its highest point. 

To sum up Griffith's contribution to the making of motion pic- 
tures and thus to editing, Lewis Jacobs may again be quoted: "It is 



Nov., 1942] CUTTING AND EDITING PICTURES 291 

that the primary tools of the screen medium are the camera and the 
film, rather than the actor; that the subject matter must be con- 
ceived in terms of the camera's eye and film cutting; that the unit of 
the film art is the shot; that manipulation of the shots builds the 
scene ; that the continuity of scenes builds the sequence ; and that the 
progression of sequences composes the totality of the production. 
Upon the composition of this interplay of shots, scenes, and se- 
quences depend the clarity and vigor of the story." Pudovkin, the 
famous Russian director, states: "Editing is the foundation of film 
art, the process of physical integration of scenes and sequences by 
which the film becomes a unified entity." It follows therefore that 
editing becomes all important. The camera, in spite of its obvious im- 
portance, becomes subordinate to the cutting process. If necessary, a 
film can be made from still pictures transposed to film and assembled 
in changing rhythm. 

The camera now has the function of an observer; an observer, 
however, who can see an object or an occurrence from all and every 
side, angle, and distance. The aim of the editing is to show the de- 
velopment of the scene, drawing the attention of the spectator to the 
details and occurrences that best represent and form the meaning 
one wishes to give to the scene. In doing this, the dramatic tensions 
are created, reinforced, or re-directed. One might compare the proc- 
ess to the job of an announcer at a football game. He observes the 
game from the most advantageous point. He does not give a de- 
tailed account of all the things happening on the field ; or rather, he 
chooses those events that give meaning to the occasion. If the action 
is fast and exciting, he will hurry in his commentary, speaking in fast, 
short sentences that give close-up impressions. If the game is slow 
and uneventful, he will describe the general atmosphere, giving long- 
shot impressions. Just as a good announcer, by selecting the out- 
standing happenings the highlights of the event can give his 
listeners the impression of the entire game, so the film editor, by 
proper choice of his material, by using the right angles for the right 
piece of action, will convey to his audience the strongest dramatic 
interpretation of the material. 

This leads to the subject of rhythm. It has been said that rhythm 
is the skeleton of the motion picture art, to be filled out with the flesh 
of content. How is rhythm built in a picture ? The tempo of the ac- 
tion can be accelerated or slowed down in the canu-ra, and camera 
movements can have rhythmic values that become apparent aitn 
editing. The rhythmic effect is formed either by the footage that 



292 F. Y. SMITH [J. S. M. P. E. 

is, by the number of frames of each shot in a sequence; by the se- 
quence or changes of angle; by the changes in direction of move- 
ment left to right against right to left, top to bottom against bot- 
tom to top, etc., by the changes of size long shot against close shot, 
etc.; or finally by any combination of these devices. 

Ten years ago the Russian technique of cutting influenced motion 
picture production and turned attention to the importance of form and 
structure through editing. Directors, writers, and producers be- 
came montage-conscious it was recognized that certain very strong 
dramatic effects could be achieved through editing and through 
montages . What is montage ? 

Montage, as the term is used in Hollywood, is a condensation of all 
the various ways of cutting, as mentioned before. The cutting is 
done partly or entirely in the optical printer, making it possible to 
show several scenes simultaneously. Condensation is here used not 
only in the technical, but also in the dramatic sense. A montage is a 
sequence in the abstract. It is the strongest form of dramatic expres- 
sion motion pictures can give. It should, therefore, be used only 
when the dramatic content of the story demands it, and not, as un- 
fortunately is often the case, when the writer does not know how to 
get over a lapse of time in the story. 

Another important discovery was that editing releases the latent 
suggestive powers of an audience, thus making a series of pictures 
impressive, eloquent, and significant. In 1921, Kuleschov, a Soviet 
film director, proved this point with the following experiment. He 
took a medium close shot of a young man who was looking down at 
something. He intercut this shot once with a scene of a plate of food. 
While running this little sequence it was quite obvious that the young 
man was hungry. Then Kuleschov intercut the same scene with a 
shot of a dead man. Now our young man appeared afraid and seemed 
to have a guilty conscience. The audience was convinced that he had 
killed the man. Finally, the scene of the young man was intercut 
with a shot of a nude woman lying on a bed. Now it became apparent 
that the young man had strictly dishonorable intentions. The very 
same shot, used in three different ways, had three different mean- 
ings a practical film demonstration of the power of suggestion. 

By the same manner of suggestion, motion pictures actually have 
created their own symbolism and sign language, a language as vivid 
and changing as slang. The funnel of an ocean liner and the wake of a 
boat are sufficient to tell that the hero has crossed the ocean; the 
gavel of the judge indicates that the court is in session ; a few shots of 



Nov., 1942] CUTTING AND EDITING PICTURES 293 

a radio tower convince us that the news has spread to the four cor- 
ners of the universe. 

And now a few words about the relationship of the editor to the 
members of the other crafts in the industry. In the early days the 
editing was done by the cameraman, the director, writer, or super- 
visor, or any combination of them. Next to the director, and often 
more than he, the writer took the most prominent part in the cutting 
of a picture. The reason for this is quite easy to understand if one re- 
members that titles had to be composed to fit the material and that 
they had to be spaced correctly. 

As pictures became longer and more elaborate, as more separate 
angles were shot, and as camera technique and optics improved, film 
editing became a specialized job. First, the cutter merely relieved 
the director of the tiresome job of sorting out and splicing film. But 
the front office soon wanted to see the assembled picture as quickly as 
possible. The cutter was entrusted with the first rough cut. It was 
soon recognized that the editor's ability to evaluate a scene was an 
important faculty that directors often lacked. 

Eventually the editor gave the picture its final form, strengthening 
continuity, progression, and logic; tightening story and plot; cover- 
ing up technical mistakes and bad acting. The technical knowledge 
of what actually can be done by arranging various pieces of film de- 
veloped into a creative ability. In the old days, a personal creative 
relationship existed between editor and director and writer, but as the 
process of motion picture making became industrialized, this rela- 
tionship disintegrated. Today, in most cases, a director seldom 
chooses his own film editor and the editor has scant opportunity to 
confer with the director and practically no chance to discuss story 
points with the writer. 

In conclusion, it will be appropriate to quote from Frank Capra, 
one of the foremost directors of the present time and former President 
of the Screen Directors Guild: "The motion picture, as a creative 
art, peculiarly has need for many contributors, of whom the film 
editor is of foremost importance. Without his sympathetic under- 
standing of theme, his sensitive appreciation for mood, his instinct 
for dramatic effect, and his sense of timing for comedy, every motion 
picture would suffer immeasurably." 

The writer wishes to thank two members of the Society of Motion 
Picture Film Editors, Herman J. Kleinhenz and Walter Stern, for 
their cooperation and for their permission to use some of their ma- 
terial in this paper. 



PROGRESS IN MOTION PICTURE INDUSTRY* 
REPORT OF THE PROGRESS COMMITTEE, 1940-41 

Summary. No report of the Progress Committee has been presented to the Society 
since that covering the year 1939, which was published in the JOURNAL in May, 1940. 
Accordingly, the present report covers the years 1940-41. This report, like previous 
ones, includes the following classifications: (I) Cinematography: (A) Professional, 
(B) Substandard; (II) Sound Recording; (III) Sound and Picture Reproduction; 
(IV) Television; ( F) Publications and New Books. 

The period covered by this report ends with the entrance of the 
United States into World War II, and during these two years the 
facilities of the equipment manufacturers have been gradually turned 
to production for the war effort. As a result there is little to report in 
the way of new equipment. Specialized instruments and methods 
developed for war photography in England have been the subject of 
a number of papers, particularly in the Photographic Journal, and a 
list of these is included in the final section of this report. 

The Committee wishes to acknowledge especially the contributions 
of the following individuals and organizations: Drs. W. B. Rayton 
and A. F. Turner of the Bausch & Lomb Optical Company, Robert 
E. Shelby of the National Broadcasting Co., Inc., H. Barnett of the 
International Projector Corp., and Charles W. Handley of the Na- 
tional Carbon Co. Because of the war there have been no reports 
available from members abroad. 

G. A. CHAMBERS, Chairman 

F. T. BOWDITCH M. S. LESHING 

G. L. DIMMICK G. E. MATTHEWS 
J. A. DUBRAY D. R. WHITE 

SUBJECT CLASSIFICATION 

(I) Cinematography 

(A) Professional 

(1) Emulsions 

(2) Cameras and Accessories 

(3) Lenses and Surface Treatments 

(4) Studio Lighting 

(5) Color 

* Received August 15, 1941. 
294 



PROGRESS IN MOTION PICTURE INDUSTRY 295 

(5) Substandard 

(1) Films 

(2) Cameras and Accessories 
(5) Projectors and Accessories 

(//) Sound Recording 

(1) General 
(2} Equipment 

(///) Sound and Picture Reproduction 
(IV) Television 
(V) Publications and New Books 

(I) CINEMATOGRAPHY 

(A) Professional 

A short time prior to the last Progress Report the advances in mo- 
tion picture films had been chiefly in the field of negative emulsions 
where increased speed had been combined with suitable contrast and 
grain characteristics. Minor additional changes and adjustments 
have been made in this field during the past two years but the main 
progress has been in the realm of positive materials which had been 
essentially unchanged for a considerable period of time. 

(1) Emulsions. Progress in this field started in sound recording 
work where fine-grain stocks were tested experimentally. Pictorial 
tests were made with some of these stocks which showed that the 
field of their usefulness was not limited to sound recording but that 
they could be used also for release work with an overall improve- 
ment of quality. The status of the work in this field is summarized 
to the fall of 1939 in a paper by Daily published in the JOURNAL in 
January, 1940. l 

Following these first steps, improvements were made and new 
fine-grain sound and positive stocks were introduced both by DuPont 
and Eastman. The DuPont Company introduced the 226 type which 
was first used for background projection work and sound recording, 
and then, as further advances were possible, introduced the 225 type, 
fine-grain release positive, and the 230 type, a low-contrast fine-grain 
sound recording stock particularly designed for variable-density 
recording. The 228 type, master positive, carried these emulsions 
into this field of work. The Eastman fine-grain release positive, type 
1302, was introduced in the fall of 1940, being followed by a fine-grain 
sound negative for variable-density recording, carrying the code 
number 1370. This latter film was first marketed in May, 1941. 



296 PROGRESS IN MOTION PICTURE INDUSTRY [j. S. M. P. E. 

The speed of these new fine-grain release positive films is about one- 
quarter that of the older type of positive. The new emulsions are 
characterized by high resolving power and image sharpness. Proc- 
essing techniques and conditions have been discussed by Shaner 2 and 
by Wilkinson and Eich. 3 Daily and Chambers 4 have discussed the 
application of fine-grain films to variable -density recording. 

An advance in the coating of a protective layer over the emulsion 
following the normal photographic processing operations was out- 
lined by Talbot. 5 Unlike earlier coatings, this particular one is re- 
movable in an alkaline solution and the film can then be recoated, 
thus greatly extending the life of the film during which the emulsion 
itself can be kept free from scratches and abrasions. 

(2) Cameras and Accessories. Additional units of the Twentieth 
Century camera described in earlier reports have been manufactured 
and are in use. Details regarding the camera are given in the JOURNAL 
by Clarke and Laube. 6 

Several new, very compact slating devices have been described. 
These units, usually attached to the camera, provide translucent data 
which are photographed through the camera lens. The Twentieth 
Century camera includes such a device, and another has been de- 
scribed by Gilbert. 7 

A novel method of obtaining great depth of field has been proposed 
by Goldsmith. 8 In this increased range (IK) system a method of 
regional lighting of the set in synchronism with differential focusing 
during each frame exposure is employed. Another attack on this 
same problem is made in the Electroplane camera 9 which incorporates 
an oscillating element in the lens. This element is driven electrically 
over a total distance of 0.3 mm many times during the exposure 
of each frame. 

(3) Lenses. The use of surface-treated lenses to increase speed 
and contrast has become rather widespread in the two-year period, 
1940-41. Firms that have either announced the provision of surface 
treatment in certain optics of their own manufacture, or have solicited 
work to be surface-treated are the following: Bausch & Lomb Optical 
Co., Rochester, N. Y.; General Electric Co., Schenectady, N. Y.; 
National Research Corp., Brookline, Mass.; RCA Manufacturing 
Co., Indianapolis, Ind.; Yard Mechanical Laboratories, Pasadena, 
Calif. 

The surface treatment of lenses is carried out commercially in one 
of the following ways : (a) by chemical means in which some constitu- 



Nov., 1942] PROGRESS IN MOTION PICTURE INDUSTRY 297 

ents of the glass are leached out to a certain depth below the sur- 
face, and (b) by physically applying a film of material of low refrac- 
tive index to the glass surface. Frank L. Jones 10 describes chemical 
methods for optical glasses and F. H. Nicoll 11 announces anew chemi- 
cal method using hydrofluoric acid. In the second method (b) films 
are applied in high vacuum, for instance, as described in U. S. Patent 
2,207,656 (July 9, 1940). Both W. C. Miller 12 and RCA claim im- 
provements in the evaporation process to increase the durability of 
the films. The method of surface treatment using films built up of 
monomolecular layers of metallic soaps described by K. B. Blodgett 1 * 
does not appear to have been adopted commercially. 

The action of films in increasing transmission by reducing surface 
reflection loss is discussed popularly by A. F. Turner. 14 W. B. Ray- 
ton 15 describes the application of films in projection optics and C. H. 
Cartwright 16 gives data on a treated camera objective. Charles G. 
Clarke 17 and Gregg Toland 18 relate experiences in shooting with 
treated camera optics. 

(4) Studio Lighting. The high-intensity carbon arc continues to 
be the principal light-source for color photography 19 and is being 
used also to an increasing degree in monochrome, where it is reported 
to bring out textural values and to permit the use of smaller aper- 
tures as required by increased-depth technique. 20 A number of re- 
finements in the design of the carbon arc lamps used for set illumina- 
tion have been made during the period under review, although none 
involves basic changes in the nature of this equipment. An important 
advance in this connection is the elimination of objectionable lamp 
noise through rubber mounting of the feed-motors, the use of an im- 
proved negative carbon, and a sound-proofing treatment of the lamp- 
house. 21 The use of a triple-head projector 22 has expanded the scope 
of background process photography for both color and black-and- 
white, and a new 16-mm super-high-intensity studio positive carbon 
capable of burning at currents as high as 225 amperes is finding con- 
siderable use in this type of work! 23 New lamp equipment 19 for use 
with process projection makes possible the transition from one car- 
bon size to another with only momentary delay, as positive carbons 
are positioned through an automatic photronic control. This lamp 
will accommodate carbons from 13.6 to 16 and 18 mm in diameter 
with their various negative carbons. The positive feed is water- 
cooled. An increased amount of process slide projection is being done 
with the larger size biplane filament tungsten lamps made available 
for this'purpose. 19 - 23 



298 PROGRESS IN MOTION PICTURE INDUSTRY [j. s. M. P. E. 

A trend is also reported toward the increased use of properly cor- 
rected incandescent lighting for color photography where smaller 
units are required, on certain types of close-ups and on small sets. 20 
Daylight fluorescent lamps were also introduced to studio technique 21 
where the high diffusion and freedom from glare is suited to general 
lighting not requiring projection. 

An item of particular interest in special fields of photographic il- 
lumination is the use of the Edgerton high-speed mercury lamp, 19 
which is capable of photographing a single frame in a time-interval 
of only Viso.ooo second and is thus adapted to "slow-motion" photog- 
raphy at a frame rate determined primarily by the mechanical limita- 
tions of film movement. 

(5) Color. Experimental work looking toward the use of a 35-mm 
monopack-type film for original exposure has been in progress. That 
considerable success is being achieved was demonstrated by results 
shown at the Spring meeting of the Society in 1942 by the Techni- 
color Motion Picture Corporation. 

Considerable work has been done also on the problem of producing 
35-mm three-color prints from 16-mm Kodachrome originals. Sev- 
eral shorts produced by this method using Technicolor for the 35-mm 
imbibition prints have been released by Warner Bros. 

(B) Substandard 

(1) Films. Agfa introduced two new emulsions in this field during 
the period a 16-mm high-resolving sound recording film and twin-8- 
mm Triple-5 Pan. The 16-mm sound recording film was designed 
primarily to improve the available quality of variable-area records 
but, of course, can be used for other purposes by proper selection of 
processing conditions. The twin-8 mm Triple-5 Pan is a high-speed 
film for use in black-and-white photography in the 8-mm field. 

In 1940 DuPont improved the 16-mm films that it sold by the 
introduction of the 321 -type which continued to carry the name of 
regular panchromatic reversal, and the 302-type superior panchro- 
matic reversal. 

In 1941 the advances which had been made in fine-grain positive 
stocks were made available in the 16-mm field by the introduction of 
the 605-type, fine-grain positive by DuPont and type 5302 fine-grain 
positive by Eastman. 

The quality of Kodachrome images was improved by a new method 
of processing, as reported by Mees at the 1940 Christmas Lectures at 



Nov., 1942] PROGRESS IN MOTION PICTURE INDUSTRY 299 

the Franklin Institute (Philadelphia). The older method required 
three separate color developments on three machines, with a drying 
after each development. Continuous processing on one machine is 
possible by the improved procedure. The assigning of the three dyes 
to their correct layers depends upon the sensitivity of the three emul- 
sions rather than the position of the layers in the depth of the film. 

The sequence of the processing operations is as follows: (1) de- 
velopment to a negative; (2) exposure through the base side to red 
light; (3) development of a cyan image in the lower emulsion layer; 
(4) exposure from the top side to blue light; (5) development of a 
yellow dye image in the top emulsion layer; (6) development of a 
magenta dye image in the middle layer; (7) removal of the silver 
from all three layers; (8) fix; (9) wash; (10) dry. 

Two sizes of color prints (2x and 5jc) from miniature Kodachrome 
transparencies were announced in August, 1941. These were made 
on an opaque safety support and were exposed and processed by the 
Eastman Kodak Company. Commercial color enlargements for 
advertising or lobby display purposes were introduced at the same 
time. A similar type of support was used but improved color cor- 
rection resulted from the use of a special black-and-white mask printed 
on panchromatic film from the original sheet Kodachrome. These 
enlargements, known as Kotavachrome, were supplied in several 
sizes to a maximum of 30 X 40 inches. 

A new still process of color photography was announced in Decem- 
ber, 1941, under the name "Kodacolor." It uses roll film which is 
exposed in the camera in the usual way. After development by the 
manufacturer, negatives are produced which have colors complemen- 
tary to those of the original subject, and from these negatives, color 
prints are made on paper. The film has three light-sensitive layers, 
in each of which are suspended minute particles of organic compounds 
in which the couplers are dissolved. After exposure, the film is de- 
veloped and the oxidation product of the developer penetrates the par- 
ticles and reacts with the couplers, each in its own layer, to form a dye 
image. The printing material is coated with a similar set of emul- 
sions. Prints are made by projection and are of the same width, 
2 7 /s inches, regardless of the size of film used. 24 

(2) Cameras and Accessories -The magazine-loading principle 
was extended to the 8-mm camera field in the Cine^Kodak Eight, 
model 90, announced in July, 1940. The magazine contains 16-mm 
film which is slit after processing. The magazine is suitably marked 



300 PROGRESS IN MOTION PICTURE INDUSTRY [J. s. M. P. E. 

so that the user can expose it properly, running the film through the 
camera once, reversing the magazine in the camera, and subsequently 
exposing the second side. 

A professional type 16-mm camera incorporating pilot-pin regis- 
tration was produced by Bell & Howell. 20 While only one unit was 
manufactured, it has been used for commercial production. The 
manufacture of additional units must necessarily await available ma- 
terials after the war. This camera is in every way a miniature of the 
well known Bell & Howell 35-mm camera. 

A review of the problems related to lens design for sub-standard 
cameras, together with a description of various commercial lenses 
available, has been given by Kingslake. 25 

(3) Projectors and Accessories. A non-intermittent 16-mm motion 
picture projector was designed by F. Ehrenhaft and F. H. Back. 26 
Optical compensation is effected by means of a rotating glass prism 
placed between the film and the projection lens. The prism has twelve 
faces and the distance between opposite faces is 41 .5 mm. The relation 
between image displacement and rotational angle of the prism is sub- 
stantially linear. To prevent misalignment of the prism faces with 
respect to the film frames during the rotation of the prism, it is driven 
by the film itself. 

A new line of 16-mm sound projectors identified as F, FB, FB-25, 
FS-10, and FB-40 were introduced by Eastman Kodak Company. 27 
The first three models operate on alternating or direct current while 
the last two operate only on a 50 to 60- cycle 100 to 125-volt supply. 
On all models, a governor of the electrical vibrating-reed type main- 
tains constant sound speed of 24 frames per second. Fast rewind for 
all sizes of reels up to and including the 1600-ft. is provided on all 
models through the use of a clutch, rewind lever, and the main drive 
motor. Uniform speed of the film at the scanning point is assured by 
the use of a specially designed oil-damped, film-driven flywheel. 
Models F, FB, and FS-10 provide 10 watts of undistorted power. 
Model FB-25 has an output of 25 watts and model FB-40 provides 
40 watts. Projection lamps from 300 up to 750 watts are recom- 
mended. 

An extensive study has been made of procedure and equipment 
specifications for 16-mm projection by a Committee of the Society. 28 
This Non-Theatrical Equipment Committee recommends that pro- 
jectors be selected to provide, in conjunction with the screen used, pic- 
ture brightness not greater than 20 ft-lamberts and not less than 5 



Nov., 1942] PROGRESS IN MOTION PICTURE INDUSTRY 301 

ft-lamberts. When screens larger than eight or nine feet wide are 
used, the incandescent projectors conventionally employed with 
smaller screens are incapable of furnishing the amount of light recom- 
mended and an arc-lamp type of machine should be employed. A 
new high-intensity carbon trim has been made available for this pur- 
pose. 29 The light from this combination of carbons has been modi- 
fied to give a spectral quality suitable for use with colorfilm processed 
primarily for projection with incandescent lamps. These carbons, 
used in lamps especially developed for them, provide approximately 
three times as much light as was hitherto available for 16-mm pro- 
jection. 

(II) SOUND RECORDING 

(1) General. During 1940 and 1941 much attention was directed 
to the problems of recording and printing multiple sound-tracks on 
film. Control tracks of various types were developed in the labora- 
tories and were tested in the studios under production conditions. 
Stereophonic recording on film was accomplished and was successfully 
demonstrated. 

The trend toward fine-grain film continued during the past two 
years. The speed of fine-grain film was increased and the objection- 
able brown color was eliminated. Although work continued on the 
high-pressure mercury-vapor lamp for exposing fine-grain film, there 
was a growing desire to use incandescent lamps for original recording. 
The increased efficiency obtained by coating the recording optics to 
reduce reflections greatly relieved the exposure problem. 

The effect of ultraviolet light on variable-density recording and 
printing was studied in the laboratory. 30 An ultraviolet variable- 
density recording system utilizing quartz lenses 31 was built and tested 
under studio production conditions. These tests showed an improve- 
ment in both wave-shape and frequency response. The noise level 
from the film was not affected by the wavelength of the exposing 
light. 

A careful study of the noise-reduction amplifier was made, 11 ' M and 
the desired characteristics were expressed in terms of promptness of 
opening and closing, peak reading ability, and filtering. Many cir- 
cuits were analyzed and the requirements for variable-area and vari- 
able-density were compared. ' 

(2) Recording Equipment. A line-type microphone for speech 
pick-up was developed by RCA. 14 It has a pick-up angle of approxi- 



302 ' PROGRESS IN MOTION PICTURE INDUSTRY [J. S. M. P. E. 

mately 30 degrees at medium and high frequencies and approxi- 
mately 60 degrees at low frequencies. The frequency response is rea- 
sonably flat between 150 and 5000 cps. A model was sent to Holly- 
wood for test. 

ERPI developed a multiduty motor system 35 for use in (1) original 
recording on a studio stage, (2} original recording on location, (3) re- 
recording, and (4) background projection. The new system provides 
more power for camera motors without increase in size, more accu- 
rate interlock, and a number of accessory features which add to the 
convenience and reliability of operation. 

RCA developed a three-layer dichroic reflector for use in photocell 
monitoring systems. 36 It has a transmission of 95 per cent at 4400^4 
and a reflectivity of 65 per cent at 7340^4 . When placed in the light 
path of a recording optical system the new reflector transmits the 
actinic rays and reflects the rays to which a caesium photocell is 
most sensitive. 

A new noise-reduction unit designated as RA-1124 was introduced 
by ERPI. 37 This unit delivers sufficient bias current to give closure 
to any Western Electric light-valve circuit and will also operate the 
Western Electric variable-area shutter. Peak-type operation is em- 
ployed and the timing is easily changed for standard or push-pull 
variable-area or variable-density records. (Photo, p. 144, Feb., 
1942.) 

A precision direct-reading densitometer was developed by Afga 
Ansco. 38 It utilizes a simple electronic arrangement designed to give 
a uniform scale over a density range of to 3.0. The color-response 
represents a compromise between the response of the eye and that of 
positive film. The scale is calibrated to read visual diffuse density. 
(Photo, p. 167, Feb., 1942.) 

Headphones having high-fidelity characteristics were offered by 
RCA. 39 These phones combine high sensitivity and low distortion 
with a good frequency response. They are comfortable to wear and 
are readily serviced. (Photo, p. 322, Sept., 1941.) 

ERPI developed an amplifier (RA-1111-A) for the application of 
stabilized feed-back to the RA-1061 and other ERPI light- valves. 40 
The amplifier is used to obtain controlled damping of the mechanical 
resonance without distortion and temperature variations inherent in 
mechanical damping methods. Light- valves that are tuned to 10,000 
cps will now produce uniform response from 40 to 8000 cps. (Photo, 
p. 248, March, 1942.) 



Nov., 1942] PROGRESS IN MOTION PICTURE INDUSTRY 303 

The Canady Sound Appliance Company announced a new profes- 
sional-type 16-mm recorder 41 built to meet the requirements of the 
commercial producer of 16-mm films. The recorder is provided with 
a rotary stabilizer of the dry type which is not affected by climatic 
conditions. A gaseous discharge lamp is used as a light-modulator 
and the output is focused on the film by an optical unit of high re- 
solving power. Frequencies from 30 to 9000 cps have been recorded 
on a standard recording emulsion. (Photo, p. 208, Aug., 1940.) 

OH) SOUND AND PICTURE REPRODUCTION 

(1) General. Limitations of the single-channel reproducing system 
were generally recognized and several methods were developed for 
increasing the volume range and the acoustic spread of the sound in 
the theater. 42 - 43 Walt Disney's Fantasia** was an outstanding ex- 
ample of the added realism accomplished through the use of a three- 
channel reproducing system. This system employed four double- 
width sound-tracks. Three of these were used for music and dialog 
and one was a control-track for regulating the volume of each of the 
three reproducing channels. The special sound reproducer and other 
units of the equipment were developed by RCA in cooperation with 
Disney engineers. 

The Bell Telephone Laboratories developed a system for stereo- 
phonic reproduction 45 from film, and successfully demonstrated it in 
New York and Hollywood. The system employed four variable-area 
sound- tracks, 46 one of which was used for controlling the volume from 
the other three. The three program tracks were separately recorded 
from three microphones spaced across the stage. Separate reproduc- 
ing channels carried the output of the sound-tracks to three loud 
speakers having the same relative positions as the microphones. The 
frequency response of the complete system extended from 50 to 15,000 
cps. By compressing the original recording and expanding it in re- 
production, a volume range of 100 db was realized. 

A sprocket-hole control-track system was developed by RCA Manu- 
facturing Co., Inc., for switching on additional speakers for 
music and for regulating the volume from a multiple-speaker repro- 
ducing system. One advantage of this system is that the release 
print is interchangeable with standard release prints. The sprocket- 
hole control-track also eliminates the necessity for changing existing 
film standards and the obsolescence of reproducer equipment. Warner 



304 PROGRESS IN MOTION PICTURE INDUSTRY [j. s. M. p. E. 

Bros, studio has applied this system to a number of pictures 43 and are 
testing it in three large theaters. 

ERPI developed a reproducing system utilizing a 5-mil control- 
track located between the sound-track and the picture. One or more 
variable-frequency tones are recorded on the narrow track for the 
purpose of regulating the volume of the sound and for switching the 
side speakers on and off. The advantages of this system are that it 
can be made to perform several functions, and the control can be 
operated very fast. 

Projection lenses with coated glass surfaces continued to gain in 
popularity during 1940 and 1941. The increase in light transmission 
due to the surface treatment varied from 15 to 30 per cent depending 
upon the number of elements in the lens. Improved contrast ap- 
peared to be as important as the gain in light. New coated projec- 
tion lenses were offered for sale by the Bausch & Lomb Optical Com- 
pany. Also a service for coating used projection lenses was offered by 
RCA Manufacturing Co. Inc., Indianapolis; Vard Mechanical Labo- 
ratory, Pasadena, Calif.; and the National Research Corporation, 
Brookline, Mass. 

Continued improvement in light-sources for the projection of 35- 
mm motion picture film was characterized by the appearance of a 
series of improved carbons giving more and cheaper light, new 
lamps, particularly in the "One Kilowatt" classification, adapted to 
supply economical white light to the smaller theaters, and a renewed 
interest in automatic control mechanisms for accurately maintaining 
carbon position. 

The "One Kilowatt" direct-current lamps employ a 7-mm copper- 
coated positive carbon burned at 27.5 volts and 40 amperes, the 
low voltage being made possible through the development of a special 
negative carbon 47 which permits the use of a very short arc length 
without the development of the carbide tip obtained when earlier 
types of negative carbons are so operated. An a-c type of "One 
Kilowatt" arc also was made available, 48 operating on 96-cycle al- 
ternating current delivered by a special generator. The choice of this 
frequency was determined by the fact that one full cycle occurs during 
each 90-degree shutter opening of a standard 24-ftame-per-second 
projector, so that the flicker ordinarily considered characteristic of 
alternating current arcs is eliminated. 

A new 8-mm copper-coated positive carbon 49 was introduced, char- 
acterized by a 60 per cent increase in crushing strength, giving added 



Nov., 1942] PROGRESS IN MOTION PICTURE INDUSTRY 305 

resistance to the action of carbon clamping devices, a burning life ap- 
proximately 20 per cent longer, and an increased current-carrying 
capacity giving 25 per cent more maximum light than that of its 
predecessor. 

For the inclined-trim condenser-type lamps, a new regular 13.6- 
mm positive carbon was introduced, 60 having 50 per cent longer life 
with the same light as the carbon it replaced, plus a higher current 
capacity resulting in more light at 150 amperes than was available 
from the old super 13.6-mm carbon at 180 amperes. As an aid to the 
largest theaters, a new super 13.5-mm carbon for operation at 170 
amperes has very recently been introduced, 61 giving almost 25 per cent 
more light than the old super at 180 amperes, and 15 per cent more 
than the new regular just described at its maximum current of 150 
amperes. 

An increased consciousness of the importance of the spectral qual- 
ity of projector light-sources as they determine the color of the screen 
image is evidenced by the Society's participation in the activities of 
the Inter-Society Color Council 62 and by the interest shown in screen 
light color determinations. 63 

Development work with methods of arc control employing photo- 
electric cells and bimetallic thermostats 54 has demonstrated that 
automatic devices of simple construction are capable of maintaining 
constant the intensity, distribution, and color of the light on the pro- 
jection screen. The more efficient the optical system becomes, the 
less the tolerance of the carbon position, so that it is anticipated that 
the commercial development of control devices of this type will per- 
mit a considerable advance in projection efficiency as realized in the 
average theater. 

(2) New Equipment. The International Projector Corporation 
introduced a Simplex double-film attachment. 65 This unit was de- 
signed for use with the Simplex 4-Star sound system where separate 
picture and sound prints are run for reviewing purposes in studios or 
for showing pre-release prints in theaters. For double-film operation 
the lower magazine provides space for three 1000-ft reels. For ordi- 
nary sound and picture projection there is ample space in the lower 
magazine for a 2000-f t reel. 

A 35-mm motion picture projector with improved mechanism 
was offered by the Century Projector Corp. 6 * Greater accuracy in 
projection, increased operating efficiency, low maintainance, and 
longer life are claimed as the result of accurate design and precision 



306 PROGRESS IN MOTION PICTURE INDUSTRY tf. s. M. P. E. 

workmanship. Sealed-for-life ball-bearings are used for the high- 
speed shafts and oil-less sleeve bearings for the low-speed shafts. The 
projector is equipped with a double-shutter mechanism having 67- 
degree blades running in opposite directions. 

A coin-operated 16-mm sound movie projector was developed for 
the Mills Novelty Company under the trade name of Panoram. In 
a large cabinet are housed a type RCA-PG-170 16-mm sound-picture 
projector and a 25- watt amplifier which drives six cone speakers. 
Forced draft ventilation is used for cooling the projector as well as the 
amplifier. The 16-mm prints, which are treated to prevent sticking, 
are spliced into an endless loop and are kept in a special continuous- 
feed type magazine. The picture portion of these prints is obtained 
by optically reducing 35-mm negatives, whereas the sound-track is 
contact printed from directly recorded 16-mm sound negatives. 
Rear projection is used to permit viewing the picture on a translucent 
screen incorporated in the cabinet. 

(TV) TELEVISION 

In an order dated May 3, 1941, the Federal Communications 
Commission authorized commercial television broadcasting to become 
effective July 1, 1941. On that date one station, WNBT, started 
commercial service in the New York area; a second station, WCBW, 
began regular program service under a commercial construction per- 
mit ; and several others in various cities inaugurated regular program 
operation under existing experimental licenses. Subsequently to 
that date, television broadcast service on either a commercial or ex- 
perimental basis has been provided in the Philadelphia, Schenectady, 
Chicago, and Los Angeles areas in addition to New York City. The 
FCC Rules and Regulations require a minimum of fifteen program 
hours per week for commercial operation, and specify technical stand- 
ards essentially as recommended by the National Television Systems 
Committee, and industry group set up jointly in 1940 by the Radio 
Manufacturers Association and the Federal Communications Com- 
mission to study the problems of technical standards. These stand- 
ards were given in detail in a report by the Television Committee of 
the Society in the July, 1941, issue of the JOURNAL. 

In spite of the serious handicap caused by shortages of essential 
materials for both receivers and transmitting equipment, commer- 
cial television has made notable progress. It is hoped that it will be 
able to continue in spite of the war, at least on a modest scale, so that 



Nov., 1942] PROGRESS IN MOTION PICTURE INDUSTRY 307 

it may be expanded rapidly when the war is over. This is in contrast 
to the situation in England where television was shut down com- 
pletely, for the duration, on the first day of the war. 

Television broadcasting is aiding in various ways in the nation's 
civilian defense effort. In New York City, for example, it is being 
utilized by the police department as a medium for giving official 
training to the air-raid wardens in that area, as well as to the thou- 
sands of persons viewing these official lessons on home receivers. 
These training programs from station WENT are being re-broadcast 
by station WPTZ in Philadelphia and station WRGB in Schenectady 
for the benefit of air-raid wardens and the public in those areas. 
Television receivers have been installed in all precinct police stations 
in New York City for the training of air-raid wardens and police 
personnel. 

At the present time, it is estimated that there are approximately 
five thousand television receivers in the New York Metropolitan 
area, four hundred in the Philadelphia area, one hundred in the Chi- 
cago area, one hundred fifty in the Schenectady area, and four hundred 
fifty in the Los Angeles area. Since the last report of this Committee, 
several notable improvements in television receiver design have been 
made, including the demonstration of a projection- type receiver for 
home use producing a picture of good brilliance on a translucent 
screen, IS 1 /* inches X 18 inches. Substantial progress has been 
made in circuit engineering of receivers, and prices have been reduced 
from the levels at which receivers were first introduced to the public. 
Very few receivers have been available for retail sale for six months 
or more, however. 

Progress in television broadcasting has been highlighted by im- 
proved studio techniques and facilities and by extension of the scope 
of outside pick-ups. The latter has been made possible primarily by 
the development of the orthicon camera for television pick-up under 
adverse light conditions. With this camera it is possible to televise 
most public events (boxing and wrestling bouts, baseball games, 
track meets, etc.), using only the lighting provided for the benefit of 
the spectators who are present, and programs of this sort are now an 
important part of the regular television schedule. New compact 
television camera and pick-up equipment has been developed and 
described in the literature by both the Dumont and RCA Manu- 
facturing Companies, that of the latter company utilizing orthicon 
camera tubes. New television studio plants have recently been put 



308 PROGRESS IN MOTION PICTURE INDUSTRY [j. s. M. P. E. 

in operation by the General Electric Company in Schenectady and 
the Don Lee Company in Los Angeles, and new facilities are under 
construction by Philco in Philadelphia. 

Television network operation has become a reality with the regular 
re- transmission of programs from the NBC station WNBT in New 
York, by station WPTZ of the Philco Radio & Television Corpora- 
tion in Philadelphia. Earlier experiments in the re-transmission of 
WNBT programs by the General Electric station WRGB in Schenec- 
tady have also been resumed. 

Two developments were announced leading toward possible solu- 
tions of the problem of providing a more comprehensive television 
network service. One of these was the experimental work by the Bell 
Telephone Laboratories on the transmission of television signals over 
800 miles of coaxial cable, looped back and forth between Minneapolis 
and Stevens Point. The second was the experimentation by RCA 
Communications on the relaying of television signals by means of 
500-megacycle modulated radio repeater stations. For television 
transmission over shorter distances (within a single city), consider- 
able use is now being made of regular twisted-pair telephone cable 
circuits with special equalization. 

Further progress was made in the development of large-screen 
television for theater use, and on May 9, 1941, a demonstration was 
given by RCA in the New Yorker Theater in New York to an audience 
of twelve hundred people. A 15 X 20-ft picture was shown, having 
a screen brightness within the range considered acceptable by the 
Society for motion picture theater screens. Commercialization of 
this development has been halted temporarily, however, by the war. 

During the past year and a half there has been considerable increase 
of interest in color television by the method that employs mechani- 
cally rotated color-filters at the transmitter and receiver. Reports 
on work done by the Columbia Broadcasting System using this 
method have been made to the Society. Considerable experimenta- 
tion has been carried on by several organizations in this country and 
abroad, but it is generally felt that the work on color television has 
not yet progressed to a point where commercial standards can be 
recommended. 

The standards set up by the FCC on May 3, 1941, allowed for sev- 
eral alternative methods of transmitting synchronizing signals to the 
receivers, with the stipulation that the various alternatives used must 
give adequate performance for standard receivers. This was done to 



Nov., 1942] PROGRESS IN MOTION PICTURE INDUSTRY 309 

allow further study of the several alternative methods before final 
adoption of a single standard. The National Television System Com- 
mittee of the Radio Manufacturers' Association accordingly has been 
carrying on tests and investigations on various proposed methods 
of synchronization, but at the time of writing of this report, final 
recommendations have not been announced. 

A bibliography of important publications in the field of television 
during 1940-41 is given in the following section of this report. 

(V) PUBLICATIONS AND NEW BOOKS 

Shipment of periodicals and books from Europe to this country 
was slowed up considerably during 1940-41 by the war abroad and 
ceased entirely with the entry of the United States into the conflict, 
in December, 1941. Most of the English periodicals continued to be 
printed with good regularity. 

The more notable books which have been published since the April. 
1940, report of this Committee are the following: 

CO The Cinema Today; D. A. Spencer and H. D. Waley (Oxford University Press, 
London) . 

(2) Motion Picture Projection and Sound Pictures; J. R. Cameron (Cameron 

Publishing Co., Woodmont, Conn.}, 8th ed. 

(3) Chemistry for Photographers; A. R. Greenleaf (American Photographic Pub- 

lishing Co., Boston). 

(4) Movie Making for the Beginner; H. C. McKay (Ziff -Davis Publishing Co., 

Chicago) . 

(5) Color Movies for the Beginner; H. B. Tuttle (Ziff -Davis Publishing Co., 

Chicago} . 

(6) How to Make Good Movies (Eastman Kodak Co., Rochester, N. Y.). 

(7) Kodachrome and How to Use It; I. Dmitri (Simon and Schuster, New York). 

(8) Photographing in Color; P. Outerbridge (Random House, New York). 

Yearbooks were issued by the following publishers: 

Quigley Publishing Co., New York. 

Film Daily, New York. 

Kinematograph Publications, Ltd., London. 

Amateur Cinema League, New York. 

Abridgments, dictionaries, and compilations were issued as fol- 
lows: 
Abridged Scientific Publications of the Kodak Research Laboratories, 21 (1939), 

and 22 (1940) (Eastman Kodak Company, Rochester, N. Y.). 
A Dictionary of Applied Chemistry; T. E. Thorpe and M. A. Whitely. 4th ed., 
2 (1938) (Longmans, Green, Ltd., London). Contains a section on Film Manu- 
facture by W. Clark under "Cellulose." 



310 PROGRESS IN MOTION PICTURE INDUSTRY [j. s. M. P. E. 

The Complete Photographer; edited by W. D. Morgan (National Educational 
Alliance, Inc., Chicago}. A photographic encyclopedia containing about two 
thousand articles by authorities in various fields of photography, including 
motion pictures. Ten volumes, or about four thousand pages, when com- 
pletely issued. 

Fortschritte der Photographic, 2; E. Stenger and H. Staude (Akad. Verlag., 
Leipzig}. 

American Cinematographer Handbook and Reference Guide; J. J. Rose (Ameri- 
can Society of Cinematographer s, Hollywood}, 4th ed. 

Television Bibliography 

(1} Streiby, M. E., and Wentz., J. F.: "Television Transmission Over Wire 

Lines," Bell Syst. Tech. J., 20 (Jan., 1941), p. 62. 
(2} "Groundwork Laid for Commercial Television," Electronics, 14 (April, 1941), 

p. 66. 

(5) "NTSC Proposes Television Standards," Electronics, 14 (April, 1941), p. 18. 
(4} Fink, D. C.: "Photographic Analysis of Television Images," Electronics, 15 

(Aug., 1941), p. 24. 

(5) Fink, D. C.: "Brightness Distortion in Television," Proc. IRE, 29 (June, 

1941), p. 310. 

(6) Sarnoff, D.: "A New Era in Television," RCA Rev., 6 (July 1941), p. 3. 

(7) Maloff, I. G., and Tolson, W. A.,: "A Resume of the Technical Aspects of 

RCA Theater Television," RCA Rev., 6 (July, 1941), p. 5. 
(8} "Television Committee Report," /. Soc. Mot. Pict. Eng., XXXV (Dec. 1940), 

p. 569. 

(9} Hanson, O. B.: "RCA-NBC Television Presents a Political Convention as 
First Long Distance Pick-Up," RCA Rev., 5 (Jan., 1941), p. 267. 

(10} "Columbia Colour Television," Electronics and Television and Short Wave 
World, 13 (Nov. 1940), p. 488. 

(11} "Television Experiments on Coaxial Cable," Bell Lab. Rec., 19 (June, 1941), 
p. 315. 

(12} Kroger, F. H., Trevor, B., and Smith, J. E.: "A 500-Megacycle Radio Re- 
lay Distribution System for Television," RCA Rev., 5 (July, 1940), p. 31. 

Progress Reports 

The Photographic Journal annually prints a number of reports 
covering advances in many fields of photography. The following is 
a list of those relating to the period 1940-41, a number of which are of 
great interest as to the application of photography to the war effort 
in England: 

April, 1941 

Mortimer, F. J. : "Photography's Part in the War." 

Duncan, C. J., "Cine Camera Guns in Service with the R.A.F." 

Spencer, D. A.: "Photography Applied to Engineering." 

Matthews, Glenn E.: "Photographic Progress during 1940." 



Nov., 1942] PROGRESS IN MOTION PICTURE INDUSTRY 311 

Cartwright, H. Mills: "Photo-Engraving in 1940." 

Saunders, John E.: "Progress in Apparatus." 

Yule, W. H. Drury: "Colour Photography in 1940." 

Cricks, R. Howard: "Technical Progress in Kinematography." 

Sewell, G. H.: "Sub-Standard Kinematography in 1940." 

April, 1942 

Mortimer, F. J.: "More about Photography's Part in the War." 

Cartwright, H. Mills: "Photo-Engraving in 1941." 

Cricks, R. H. : "Wartime Progress in the Film Industry." 

Sewell, G. H. : "Sub-Standard Kinematography in 1941." 

June, 1942 

Matthews, Glenn E.: "Photographic Progress during 1941." 

REFERENCES 

1 DAILY, C. R. : "Improvement in Sound and Picture Release through the 
Use of Fine-Grain Film," /. Soc, Mot. Pict. Eng., XXXIV (Jan., 1940), p. 12. 

2 SHANER, V. C.: "A Note on the Processing of Eastman 1302 Fine-Grain Re- 
lease Positive in Hollywood," /. Soc. Mot. Pict. Eng., XXXVIII (Jan., 1942), p. 
66. 

3 WILKINSON, J. R., AND EICH, F. L.: "Laboratory Modification and Proce- 
dure in Connection with Fine-Grain Release Printing," /. Soc. Mot. Pict. Eng., 
XXXVIH (Jan., 1942), p. 56. 

4 DAILY, C. R., AND CHAMBERS, I. M.: "Production and Release Applications 
of Fine-Grain Films for Variable-Density Sound-Recording," J. Soc. Mot. Pict. 
Eng., XXXVIII (Jan., 1942), p. 45. 

6 TALBOT, R. H. : "A New Treatment for the Prevention of Film Abrasion and 
Oil Mottle," /. Soc. Mot. Pict. Eng., XXXVI (Feb., 1941), p. 191; U. S. Pat. 
No. 2, 259,009. 

6 CLARKE, D. B., AND LAUBE, G.: "Twentieth Century Camera and Accesso- 
ries," /. Soc. Mot. Pict. Eng., XXXVI (Jan., 1941), p. 50. 

7 GILBERT, F. C.: "Scene-Slating Attachment for Motion Picture Cameras," 
J. Soc. Mot. Pict. Eng., XXXVI (Apr., 1941), p. 355. 

8 GOLDSMITH, ALFRED N.: "The IR System: An Optical Method for Increas- 
ing Depth of Field," J. Soc. Mot. Pict. Eng., XXXVIH (Jan., 1942), p. 3. 

9 HOLDEN, EDWARD P., JR.: "The Electroplane Camera," Amer. Cinemat., 23 
(Feb., 1942), p. 56. 

10 JONES, F. L.: "Some Properties of Polished Glass Surfaces," /. Soc. Mot. 
Pict. Eng., XXXVII (Sept., 1941), p. 256. 

11 NICOLL, F. H.: "A New Chemical Method of Reducing the Reflectance of 
Glass," RCA Review, 6 (Jan., 1942), p. 287. 

15 MILLER, W. C.: "Recent Improvements in Non-Reflective Lens Coating," 
/. Soc. Mot. Pict. Eng., XXXVH (Sept., 1941), p. 265. 

BLODGETT, K. B.: Phys. Rev., 55 (Feb. 15, 1939), p. 391. 

14 TURNER, A. F. : Bausch & Lomb Educational Focus, 12, Spring 1941. p. 4. 

16 RAYTON, W. B.: "New Lenses for Projecting Motion Pictures," /. Soc. Mot. 
Pict. Eng., XXXV (July, 1940), p. 89. 



312 PROGRESS IN MOTION PICTURE INDUSTRY [J. S. M. P. E. 

16 CARTWRIGHT, C. HAWLEY: "Treatment of Camera Lenses with Low-Reflect- 
ing Films," /. Opt. Soc. Amer., 30 (March, 1940), p. 110. 

17 CLARKE, CHARLES G. : "Are We Afraid of Coated Lenses?" Amer. Cinemat., 
22 (April, 1941), p. 161. 

18 TOLAND, GREGG: Popular Photography, 8 (June, 1941), p. 55. 

19 Report of the Studio Lighting Committee, J. Soc. Mot. Pict. Eng., XXXV 
(Dec., 1940), p. 607. 

20 "Technical Progress in 1941," Amer. Cinemat., 23 (Jan., 1942), p. 6. 

21 ACAD. MOT. PICT. ARTS AND SCIENCES: "Report on Arc Lamp Noise Tests," 
J. Soc. Mot. Pict. Eng., XXXVI (May, 1941), p. 252. 

22 HASKIN, BYRON: "The Development and Practical Application of the 
Triple-Head Background Projector," J. Soc. Mot. Pict. Eng., XXXIV (March, 
1940), p. 252. 

23 Report of the Studio Lighting Committee, J. Soc. Mot. Pict. Eng., XXXV 
(July, 1940), p. 86. 

24 MEES, C. E. K.: "Direct Process for Making Photographic Prints in Color," 
/. Franklin Institute, 233 (Jan., 1942), p. 41. 

26 KINGSLAKE, R. : "Lenses for Amateur Motion Picture Equipment," J. Soc. 
Mot. Pict. Eng., XXXIV (Jan., 1940), p. 76. 

26 EHRENHAFT, F., AND BACK, F. G.: "A Non-Intermittent Motion Picture 
Projector," J. Soc. Mot. Pict. Eng., XXXIV (Feb., 1940), p. 223. 

27 MERRIMAN, W. E., AND WELLMAN, H. C.: "Five New Models of 16-Mm 
Sound Kodascope," /. Soc. Mot. Pict. Eng., XXXVII (Sept., 1941), p. 313. 

28 A REPORT OF THE COMMITTEE ON NON-THEATRICAL EQUIPMENT: "Recom- 
mended Procedure and Equipment Specifications for Educational 16-Mm Pro- 
jection," /. Soc. Mot. Pict. Eng., XXXVII (July, 1941), p. 22. 

29 LOZIER, W. W., AND JOY, D. B.: "A Carbon Arc for the Projection of 16- 
Mm Film," /. Soc. Mot. Pict. Eng., XXXTV (June, 1940), p. 575. 

30 FRAYNE, J. G., AND PAGLIARULO, V.: "The Effects of Ultraviolet Light on 
Variable-Density Recording and Printing," J. Soc. Mot. Pict. Eng., XXXIV (June, 
1940), p. 614. 

31 DUPY, O. L., AND HILLIARD, JOHN K. : "A Monochromatic Variable-Density 
Recording System," J. Soc. Mot. Pict. Eng., XXXVI (April, 1941), p. 367. 

32 KELLOGG, E. W.: "Ground Noise Reduction Systems," J. Soc. Mot. Pict. 
Eng., XXXVI (Feb., 1941), p. 137. 

33 SCOVILLE, R. R., AND BELL, W. L. : "Design and Use of Noise-Reduction 
Bias Systems," /. Soc. Mot. Pict. Eng., XXXVIII (Feb., 1942), p. 125. 

34 OLSON, HARRY F.: "Line Microphones," J. Soc. Mot. Pict. Eng., XXXVI 
(March, 1941), p. 302. 

^HOLCOMB, A. L.: "A Multiduty Motor System," J. Soc. Mot. Pict. Eng., 
XXXIV (Jan., 1940), p. 103. 

36 DIMMICK, G. L. : "A New Dichroic Reflector and Its Application to Photo- 
cell Monitoring Systems," /. Soc. Mot. Pict. Eng., XXXVIII (Jan., 1942), p. 36. 
, 37 SCOVILLE, R. R., AND BELL, W. L.: loc. cit. 

38 SWEET, M. H.: "A Precision Direct-Reading Densitometer," /. Soc. Mot. 
Pict. Eng., XXXVHI (Feb., 1942), p. 148. 

39 ANDERSON, L. J.: "High-Fidelity Headphones," J. Soc. Mot. Pict. Eng., 
XXXVH (Sept., 1941), p. 319. 



Nov., 1942] PROGRESS IN MOTION PICTURE INDUSTRY 313 

40 ALBERSHEIM, W. J., AND BROWN, L. F.: "Stabilized Feedback Light-Valve," 
J. Soc. Mot. Pict. Eng., XXXVIH (March, 1942), p. 240. 

41 CANADY, D.: "Professional 16-Mm Recording Equipment," /. Soc. Mot. 
Pict. Eng., XXXV (Aug., 1940), p. 207. 

"REISKIND, H. I.: "Multiple Speaker Reproducing Systems," /. Soc. Mot. 
Pict. Eng., XXXVH (Aug., 1941), p. 154. 

48 LEVINSON, N., AND GOLDSMITH, L. T.: "Vitasound," /. Soc. Mot. Pict. Eng., 
XXXVH (Aug., 1941), p. 147. 

4 *GARiTY, W. E., AND HAWKINS, J. N. A.: "Fantasound," /. Soc. Mot. Pict. 
Eng., XXXVII (Aug., 1941), p. 127. 

46 FLETCHER, H.: "The Stereophonic Sound-Film System," /. Soc. Mot. Pict. 
Eng., XXXVH (Oct., 1941), p. 331. 

46 WENTE, E. C., BIDDULPH, R., ELMER, L. A., AND ANDERSON, A. B.: "Me- 
chanical and Optical Equipment for the Stereophonic Sound-Film System," J. 
Soc. Mot. Pict. Eng., XXXVH (Oct., 1941), p. 353. 

47 LOZIER, W. W., JOY, D. B., AND SIMON, R. W. : "A New Negative Carbon for 
Low-Amperage High Intensity Trims," /. Soc. Mot. Pict. Eng., XXXV (Oct., 1940), 
p. 349. 

48 KALB, W. C.: "Progress in Projection Lighting," /. Soc. Mot. Pict. Eng., 

XXXV (July, 1940), p. 17. 

49 LOZIER, W. W., CRANCH, G. E., AND JOY, D. B.: "Recent Developments in 
8-Mm Copper-Coated High-Intensity Positive Carbons," /. Soc. Mot. Pict. Eng., 

XXXVI (Feb., 1941), p. 198. 

60 JONES, M. T., LOZIER, W. W., AND JOY, D. B.: "New 13.6-Mra High-Inten- 
sity Projector Carbon," /. Soc. Mot. Pict. Eng., XXXVTI (Nov., 1941), p. 539. 

61 JONES, M. T., LOZIER, W. W., AND JOY, D. B.: "New 13.6-Mm Carbons for 
Increased Screen Light," /. Soc. Mot. Pict. Eng., XXXVHI (March, 1942), p. 229. 

" GAGE, H. P.: "Color Theories and the Inter-Society Color Council," /. Soc. 
Mot. Pict. Eng., XXXV (Oct., 1940), p. 361. 

63 NULL, M. R., LOZIER, W. W., AND JOY, D. B.: "The Color of Light on the 
Projection Screen," J. Soc. Mot. Pict. Eng., XXXVHI (March, 1942), p. 219. 

64 ZAFFARANO, D. J., LOZIER, W. W., AND JOY, D. B.: "Improved Methods of 
Controlling Carbon Arc Position," /. Soc. Mot. Pict. Eng., XXXVH (Nov., 1941). 
p. 485. 

w BORBERG, W., AND PiRNER, E. : "Simplex Double-Film Attachment," /. 
Soc. Mot. Pict. Eng., XXXIV (Feb., 1940), p. 219. 

M BOECKING, E., AND DAVES, L. W.: "Recent Developments in Projection 
Mechanism Design," J. Soc. Mot. Pict. Eng., XXXVIH (March, 1942), p. 262. 



THE PHOTOGRAPHING OF 16-MM KODACHROME SHORT 
SUBJECTS FOR MAJOR STUDIO RELEASE* 

L. WILLIAM O'CONNELL** 



Summary. A method is described of photographing professional short subject 
pictures on 16-mm Kodachrome film having edge numbers and enlarging on standard 
35-mm black-and-white film for the purpose of cutting, editing, and viewing in 
standard 35-mm studio equipment. The edited black-and-white film is used as a 
pilot film for cutting the original 16-mm Kodachrome for color separation negatives 
and the subsequent 35-mm Technicolor release prints. 

In practically all recent photographic publications whose readers 
are either professional or amateur, there have been many articles 
showing increasing interest in the possibilities of 16-mm Kodachrome 
film with regard to its application and success in making pictures 
comparable to those made on 35-mm film. Proof that comparable 
pictures can be produced lies in the fact that some major producing 
companies have already accepted a number of such short subjects 
made in 16-mm for release in 35-mm. 

Progress in any field of endeavor, whether in sports, entertain- 
ment, manufacturing of automobiles, aeroplanes, radios, or motion 
pictures, is based upon the research experimentation, and achieve- 
ments in the various parts of the field, which, when brought together, 
establish the present state of the art. 

Thanks to manufacturers of 16-mm equipment and film, light 
weight, portable, and dependable equipment has done much toward 
producing 35-mm color shorts on reasonable budgets. 

In the search for enhancement of the black-and-white short sub- 
ject release, especially "Sport Shorts," an attempt was made to 
produce them in color, using the familiar bipack 35-mm camera and 
two-color release prints. As this added considerable additional 
cost, it was decided to attempt to use 16-mm Kodachrome, which 
since has proved highly satisfactory both as to color rendition arid 

* Presented at the 1942 Spring Meeting at Hollywood, Calif.; received 
May 4, 1942. 

** Warner Bros. First National Studios, Burbank, Calif. 
314 



16-MM KODACHROME SHORT SUBJECTS 315 

as to cost. Furthermore, it provided for the professional camera- 
man and director great advantages in portability, and flexibility 
in making angle shots in fact, angles that are impracticable with 
standard 35-mm equipment can be made with this lighter equipment, 
helping to remove some of the restrictions under which the picture 
director works in planning his angle shots. 

The following describes the procedure originated by Del Frazier, 
of the Warner Brothers Studios, for using camera equipment and 
Kodachrome film in the production of short subject features to be 
released as standard 35-mm Technicolor prints 

The Cine Kodak Special, equipped with 15-mm, 25-mm, and 50- 
mm lenses has served every purpose required and has not been found 
lacking in any respect. A large field professional viewfinder has 
been added to the left side of the camera, giving more speed and 
accuracy of operation and eliminating horizontal parallax. 

A normal camera speed of 24 frames per second is used when 
recording sound in synchronism with the photography. A speed 
of 32 frames per second is used for photographing sport action shots 
to be presented with narration. For slow-motion or shots of pro- 
longed interest, such as fast swimming, diving, and golf action, etc., 
a Bell & Howell Golf Speed camera operating at 128 frames per sec- 
ond is used. A third camera is carried as a cover for action while 
reloading magazines; an Eastman Model K camera with a 15-mm 
fixed-focus lens carried in a convenient side pocket. Precautions 
should be taken in selecting group cameras with regard to the rela- 
tion between sprocket-holes and frame lines, which should be held 
to close tolerances so as to avoid frame shift when splicing and during 
subsequent projection. 

A sturdy tripod should aways be used whenever possible, but in 
many instances work can be accomplished without one, giving more 
freedom of action. This is especially true in shots close to the 
ground or taken from tree-tops, or perhaps from a step-ladder. Scenes 
taken from fast-moving cars or motorboats can be completed in the 
length of time it would take to fasten down a bulky 35-mm camera. 
But then again one must be very careful, always holding the camera 
firmly against the body, and breathing very lightly. 

As in all other operations pertaining to the photography of 16-mm 
pictures, great attention must be given to exposure, for the reason 
that an under- or overexposure shifts the color of the scene. In 
addition, it is possible that a slight loss in rendition might occur in 



316 L. W. O'CONNELL 

the Technicolor print as compared to the original Kodachrome, 
but this is negligible inasmuch as an audience is not in a position to 
make a direct comparison. A Weston reading of 8 is used in most 
instances, but wherever there is a great percentage of deep colors, 
blue sky, or heavy shadows, a slight overexposure (Weston 6) gives 
more latitude in making separations. 

An important lesson that we learned was not to work with the 
16-mm film immediately after processing. When the soft-surfaced 
emulsion is enlarged to 35-mm size and then enlarged further to 
the size of a theater screen, all the scratches and finger marks become 
sadly obvious. 

The principal advantages of editing a 16-mm film enlarged to 
35-mm black-and-white are, first, the original Kodachrome needs 
no handling other than that required in printing the 35-mm negative 
and in cutting to match the 35-mm black-and-white pilot print. 
Second, the editor can work much faster, and with the same confi- 
dence as in regular 35-mm production; the projection of his work 
can be seen in any available viewing room. To cut the original 
Kodachrome in the orthodox manner would entail endless splicing 
troubles, and the required handling of the film would ruin its value 
for reproduction. 

The enlargement of the 16-mm Kodachrome to 35-mm black- 
and-white is accomplished in a specially constructed optical printer 
in which a Bell & Howell movement is modified to take the 16-mm 
film, and the aperture is opened on the edge-numbered side to in- 
clude the full edge figures. The image is projected through a 3- 
inch copying lens to the modified aperture of a Mitchell camera 
which gives a picture size of approximately 0.600 X 0.825 inch, 
comparable to the sound-film projector aperture. The edge-numbers 
are approximately in the position of the normal sound-track, and, 
of course, are not projected. The Hanovia type AH4 mercury- 
sodium lamp is used as a printing light, and the 35-mm negative is 
produced on Eastman Background X negative stock and developed 
to a gamma of 0.6. Subsequent prints are remarkably free from 
graininess and possess a very high fidelity to the original Koda- 
chrome pictures, having been mistaken at times, for original black- 
and-white productions. 



ELIMINATION OF RELATIVE SPECTRAL ENERGY DIS- 
TORTION IN ELECTRONIC COMPRESSORS* 



BURTON F. MILLER** 

Summary. The exaggeration of sibilant speech-sounds produced when electronic 
volume compression is employed in sound-recording channels is shown to be a form 
of amplitude-selective frequency distortion, which is generated by virtue of the normal 
mode of operation of the compressor. The practical elimination of this form of dis- 
tortion is accomplished by equalization of the compressor control-rectifier input circuit, 
the amount of equalization employed being proportional to the inverse average relation- 
ship between rms speech-pressure per cycle and speech component frequency. 

Prior to the development of sound systems capable of faithfully 
recording and reproducing signals having a volume range in excess of 
35 or 40 db, it was rather generally believed that the dramatic value 
of sound pictures was definitely limited by the restricted volume 
range of the recording medium. Later, following the development 
of systems inherently capable of recording and satisfactorily repro- 
ducing a range of signal intensity comparable with that of dramatic 
dialog, it was discovered that theater reaction to such recordings was, 
in general, surprisingly unfavorable. 

The results of a study made to determine the cause of this situation 
have been previously reported in this JOURNAL by W. A. Mueller, 1 in 
which it was concluded that the general theater auditorium noise 
level sets a definite lower sound level limit for the intelligible repro- 
duction of sound, while the comfort of the theater patron appears to 
establish a corresponding upper sound level limit. The normal 
acceptable range of reproduced sound intensity levels for general 
dialog recording has, by these studies, been set at approximately 25 
db. 

In general, two basically different methods may be employed to 
limit satisfactorily the volume range of dialog recordings. The first 
of these depends upon manually controlling the relative signal levels 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received 
May 4, 1942. 

** Warner Bros. Pictures, Inc., Burbank, Calif. 

317 



318 B. F. MILLER [j. s. M. P. E. 

during recording and re-recording of the sound-track to a suitable 
overall volume range. The second method, which provides almost 
instantaneous control of signal levels and repeatedly duplicates its 
action on signals of equivalent energy levels, is provided by the elec- 
tronic type of compressor-amplifier. A third method is obviously 
afforded by combining the two basic forms of control, and represents 
a fair example of modern recording technique. 

Following the installation of electronic compressor units in all the 
recording and re-recording channels at Warner Bros, studios, it was 
consistently noted that sibilant speech sounds were reproduced with 
unusual prominence, occasionally being exaggerated to the point of 
being reproduced as harsh whistling tones when these sounds were 
stressed in the original speech. For a. time this effect was attributed 
to the residual high-frequency distortion in the recording and re- 
producing channels, and numerous circuit developments were studied 
and employed to minimize such distortion. Meanwhile, the process 
of re-recording was severely hampered, since it was found impossible 
to remove the objectionable sibilance merely by introducing a suit- 
able value of high-frequency equalization in the re-recording channel 
without, at the same time, producing a finished sound-track that was 
definitely lacking in high-frequency signal energy content. 

It was found necessary, therefore, to reduce the energy content of 
the numerous exaggerated sibilants in each reel of sound-track prior 
to re-recording by manually applying a layer of semi-opaque ink over 
each of the offending sections of the record. This process, needless 
to say, was both time-consuming and costly, since it was necessary to 
reproduce each reel of the master re-recording print several times to 
permit locating the objectionable sibilants with reference to the 
sound-start mark, and then to "paint-out" manually the corre- 
sponding sections of track. On the average, from thirty to fifty such 
spots would appear in each reel of dialog track, requiring approxi- 
mately two hours of work for the location and "painting-out" of 
these sections. 

It soon became evident that all attempts to reduce the excessive 
prominence of recorded sibilants through reduction of high-frequency 
channel distortion were accomplishing almost nothing, and that the 
cause of the difficulty being experienced was likely due to some factor 
that had thus far been completely ignored. 

In consequence of the above conclusion, attention was directed to 
the results of the several statistical studies of the spectral distribution 



Nov., 1942] 



SPECTRAL ENERGY DISTORTION 



319 



of speech energy. Notable among these is the paper by Dunn and 
White, 2 outlining the results of recent studies on this subject at the 
Bell Telephone Laboratories. The curves and data presented in the 
Dunn and White paper indicate that while no single curve can be 
taken as universally representative of the distribution of speech 
energy throughout the audio-frequency band, it is nevertheless 
possible to arrive at statistical averages of speech-energy distribution 
that can, in any event, be employed to determine the probable energy 



E 

M 
Of 
3-10 



.500 IOOO 1C 

FREQUENCY IN C.PS. 



FIG. 1. 



Average relation between rms speech-pressure per 
cycle and speech component frequency. 



relationships existing between different portions of the normal band 
of speech frequencies. 

The curve in Fig. 1 represents a "smoothed-over" relationship 
between root-mean-square speech-pressure per cycle, and frequency, 
which has been prepared from data taken from the Dunn and White 
paper. The averaging process employed in obtaining this curve 
ignores the normal differences in energy distribution between male 
and female voices, as well as the departures from a smooth curve that 
actual measurements of speech-energy distribution indicate. In 
view of the use that is to be made of the above curve, however, this 
averaging process is believed legitimate. 



320 B. F. MILLER [J. S. M. P. E. 

Assuming this curve to be representative of the relative pressure 
distribution with frequency for the various frequency components of 
each spoken work, it may, in general, be observed that the pressures 
corresponding to the lower-frequency vowel sounds of speech are 
many times higher than those corresponding to the higher-frequency 
sibilant sounds. Correspondingly, the low-frequency components of 
speech signal voltage in the recording channel will normally be many 
times greater in amplitude than the high-frequency components. If 
the total amplification of the recording channel is made an inverse 
function of the instantaneous signal voltage at some point of the 
recording circuit, as is done when electronic compression is employed, 
the channel amplification may be expected to be notably higher when 
speech sibilants are being recorded than when vowel sounds are tra- 
versing the recording system. Such a condition gives rise to a form 
of amplitude-selective frequency distortion, which will be incapable 
of correction by any straightforward process of signal-frequency 
equalization during reproduction of the sound record. 

This situation may, perhaps, be clarified somewhat by a simple 
analytical treatment of the several factors involved. In a normal 
amplifier system the overall amplification may be defined as the 
ratio of the amplifier output voltage E to the amplifier input voltage 
E . This ratio may be a function of signal frequency, but throughout 
the working range of signal input levels, is independent of signal 
voltage. Presuming the amplification to be made independent of 
frequency as well, the ratio of amplifier output to input voltages may 
be expressed as 

I - * ) 

where u a is a constant. 

In the case of the electronic compressor, however, the amplification 
obtained is purposely made a function of a tube electrode control- 
voltage e c . This control- voltage is normally derived by rectifying a 
portion of the compressor output voltage, which is then so applied to 
the amplifier tubes that the expression for amplification through the 
compressor generally takes the form 

EC _ U e U c (2) 

Et (*)* 



where u c and ki are constants, and where the exponent m varies from 
approximately zero at low values of E to a positive limiting value 
approached as E assumes progressively higher values. 



Nov., 1942] 



SPECTRAL ENERGY DISTORTION 



321 



Solving eq. 2 for the ratio </, in terms of the input voltage E it 

E 

^ = .(.-)" (3) 

*U 

where u e is a constant, and n m/(m + 1). A curve showing the 
actual relationship between compressor amplification and input 
signal level at constant frequency for the compressors employed at 
Warner Bros, studio is shown in Fig. 2, the amplification being ex- 
pressed in decibels rather than in the arithmetical ratio employed in 
eq. 3. It will be noted that throughout the greater portion of the 




-52 -46 

COMPRESSOR 



I. -40 -36 -32 

INPUT LEVEL IN DB. 



FIG. 2. Relation between compressor amplification and 
compressor input signal level. Reference level employed is 6 

mw. 

compression range of input signal levels, the exponent n employed in 
eq. 3 would correspond to approximately 0.5. 

Returning to consideration of the expression for compressor ampli- 
fication, let it first be noted that the compressor input voltage corre- 
sponding to a speech signal may be written as 

Ei = A*(f) (4) 

where A is a constant for any single word, and where the function 
<r(f) expresses the relationship between probable speech-pressure per 
cycle and frequency as given by the curve of Fig. 1. 

Combining eq. 3 and eq. 4, the compressor output voltage is given 
by 

E. - .(<) +l - 



322 B. F. MILLER [J. s. M. P. E. 

In this equation the factor A n ^' 1 indicates that the amplitude of the 
compressor output signal is a non-linear function of the input signal 
amplitude, and is indicative of the fact that amplitude compression 
may be obtained. On the other hand, it is also evident that the 
normal spectral distribution function v(f) has been distorted to the 
new distribution function [0-(/)] n+1 . It is this latter distortion of the 
compressed signal that is, in general, responsible for the excessive 
prominence of speech-signal sibilants in the recorded signal. A 
simple example may serve to indicate the relative magnitude of this 
distortion. 

Assume that the word say is to be recorded. If the predominant 
frequency 3 of the sibilant 5 is assumed to be approximately 6000 cps, 
while that of the vowel q is taken as approximately 500 cps, reference 
to Fig. 1 and eq. 4 indicates that the probable amplitude of the signal 
delivered to the compressor input terminals which corresponds to the 
s sound will be approximately 15.5 db lower than that corresponding 
to the a sound. Assuming a value n = 0.5 for the exponent in the 
compressor output- voltage equation (eq. 5), the signal corresponding 
to the 5 sound at the compressor output terminals will be only 7.75 
db lower in amplitude than that corresponding to the a sound. In 
other words, the 5 sound has been exaggerated 7.75 db relative to 
the a sound. 

A clue to the method of correcting the distortion just described is 
offered by the form of eq. 2. Let it be assumed that before the com- 
pressor output voltage is delivered to the compressor control rectifier, 
the portion of the output voltage employed for control purposes is 
equalized to the form 

E.' = *(f)E. (6) 

where the form of the function i/>(/) is as yet unspecified. Sub- 
stituting eq. 6 for E in the right-hand member of eq. 2, and solving 
for the ratio E /E it one obtains 



Substituting eq. 4 in eq. 7, 
If, then, we set 



Eo 
Ei 



Nov., 1942] 



SPECTRAL ENERGY DISTORTION 



k being a constant, the right-hand member of eq. 8 is independent of 
the normal frequency distribution of speech energy. 

Electrically, the correction implied by eq. 9 is obtained by inserting 
an equalizer between the compressor output terminals and the control- 
rectifier input circuit, the loss-characteristic of this equalizer being 
designed to vary with frequency according to the inverse of the 
pressure-frequency distribution curve of Fig. 1. A schematic dia- 
gram of the modified compressor circuit is shown in Fig. 3. 




FIG. 3. Schematic diagram of modified compressor 
circuit. 



In conclusion, it may be stated that recordings made with the 
modified form of compressor are singularly free of any tendency 
toward exaggerated sibilance, yet exhibit a normal brilliance equiva- 
lent to that obtained during reproduction of normal uncompressed 
recordings. 

REFERENCES 

1 MUELLER, W. A.: "Audience Noise as a Limitation to the Permissible 
Volume Range of Dialog in Sound Motion Pictures," /. Soc. Mot. Pict. Eng., 
XXXV (July, 1940), p. 48. 

8 DUNN AND WHITE: "Statistical Measurements on Conversational Speech," 
J. Acoust. Soc. Amer., 11 (Jan., 1940), p. 278. 

FLETCHER, H..: "Speech and Hearing," D. Van Nostrand Co. (New York) 
1929, pp. 56-62. 



CURRENT LITERATURE OF INTEREST TO THE MOTION PICTURE 

ENGINEER 



The editors present for convenient reference a list of articles dealing with subjects 
cognate to motion picture engineering published in a number of selected journals. 
Photostatic copies may be obtained from the Library of Congress, Washington, D. C., 
or from the New York Public Library, New York, N. Y. Micro copies of articles 
in magazines that are available may be obtained from the Bibliofilm Service, Depart- 
ment of Agriculture, Washington, D. C. t at prevailing rates. 

Acoustical Society of America, Journal 
14 (July, 1942), No. 1 

An Absolute Pressure Generator and Its Applica- 
tion to the Free-Field Calibration of a Micro- 
phone (pp. 19-23) 



Sound Power Density Fields (pp. 24-31) 

Perturbation of Sound Waves in Irregular Rooms 
(pp. 65-73) 

Experiments with the Noise Analysis Method of 
Loudspeaker Measurement (pp. 79-83) 

American Standard Acoustical Terminology (pp. 
84-101) 

American Standard for Noise Measurement (pp. 
102-110) 

American Cinematographer 

23 (Sept., 1942), No. 9 
More Realism from "Rationed" Sets? (pp. 390- 

391, 430) 
Sound-Recording Methods for Professional 16- 

Mm Production (pp. 392-393, 427) 
Film Conservation and Substandard Film (p. 407) 

23 (Oct., 1942), No. 10 
16-Mm Gains in Studio Use (pp. 442-443) 
Shooting Action Movies from a Gunstock Mount 
(pp. 444, 453) 

British Kinematograph Society, Journal 

5 (July, 1942), No. 3 

The Soviet Film in Peace and War (pp. 65-76) 
The Optical Printer and Its Applications (pp. 77- 

86) 
324 



W. J. KENNEDY AND C. P. 

BONER 
J. H. ENNS AND F. A. 

FIRESTONE 

R. H. BOLT, H. FESHBACH 
AND A. M. CLOGSTON 

B. OLNEY 



P. FERGUSON 
J. A. LARSEN, JR. 

W. STULL 

K. O. HEZZELWOOD 

I. MONTAGU 
T. HOWARD 



CURRENT LITERATURE 325 

The Combined Services Film Studio (pp. 87-90) 

Educational Screen 

21 (Sept., 1942), No. 7 

Motion Pictures Not for Theaters (pp. 259-261, 
264), Pt. 39 A. E. KROWS 

Electronic Engineering 

15 (Aug., 1942), No. 174 
Colour and Stereoscopic Television (pp. 96-97) 

Electronics 

15 (Sept., 1942), No. 9 
Amplitude, Frequency and Phase: Modulation 

Relations (pp. 48-54) A. HUND 

An Auxiliary Circuit for C-R Photography (pp. 

59-60, 144) H. C. ROBERTS 

Communications 

22 (Aug. 1942), No. 8 
Recording Standards (p. 20) 

International Photographer 

14 (Sept., 1942), No. 8 
Night Shots in Daylight (p. 10) 

14 (Oct., 1942), No. 9 

A Lab on Wheels (pp. 3^) D. WOOD 

Cinecolor Enlargement from 16-Mm Kodachrome 

(pp. 10-11) W. T. CRESPINEL 

Conservation of Film (pp. 12, 16, 18) 

International Projectionist 

17 (Aug., 1942), No. 8 
Educational Activities of the Toronto Projection 

Society (pp. 7-8) A. MILLIGAN 

Projection Lenses with Treated Surfaces (pp. 9, 

21) A. F. TURNER 

Role of Projectionists in the U. S. Navy (pp. 10- 

11) 
Amplifier Breakdowns Averted by Use of Pilot 

Lamps as Fuses (pp. 11, 17) W. DUNKBLBBRGBR 

Underwriters Code as It Effects Projection 

Rooms (pp. 14-15, 18), Pt. IV 

17 (Sept., 1942), No. 9 

Innovation Ends Buckling of Film (pp. 7-8) L. CHADBOURNB 

Review of Projection Fundamentals. Pt. V, 

Necessary Formulas (pp. 11, 18-21) 
Underwriters Code as It Effects Projection 

Rooms (p. 16), Pt. V 



326 



CURRENT LITERATURE 



Motion Picture Herald 

148 (Aug. 29, 1942), No. 9 

British Educational Film Expanding Despite 
War (p. 43) 

Motion Picture Herald (Better Theaters Section) 

148 (Aug. 22, 1942), No. 8 

Simplified Tests for Determining Efficiency of 
Projector Shutters (pp. 20-23) 

RCA Review 

6 (Apr. 1942), No. 4 

Low-Frequency Characteristics of the Coupling 
Circuits of Single and Multi-Stage Video Am- 
plifiers (pp. 416-433) 

A Discussion of Several Factors Contributing to 
Good Recording (pp. 463-472) 



A. FLANAGAN 



C. E. SHULTZ 



H. L. DONLEVY AND D. 
EPSTEIN 

R. A. LYNN 



W. 



SOCIETY ANNOUNCEMENTS 
ADMISSIONS COMMITTEE 



At a recent meeting of the Admissions Committee, the following applicants for 
membership were admitted into the Society in the Associate grade: 

BROWNING, ARTHUR KBLLOCK, ALAN 

190 William St., Union Carbide & Carbon Corp., 

Alexandria, Va. 30 East 42nd St., 

CARLTON F. HAYDEN New York, N. Y. 



n,;' LAUPMAN.A.L. 

Ogden Utah 1274 E. 83rd St.. 

r^ : ,n Cleveland. Ohio 

U. S. Signal Corps, 

Photographic Center, MONTAGUE, H. B. 

35-11, 35th Ave., 3327 "A" Locust St., 

Long Island City, N. Y. St. Louis, Mo. 

RAMANNA, B. 
"Padmalaya," 

1792 Sampiga Rd., 
Malleswaram P. O., 
Bangalore, India 

In addition, the following applicants have been admitted to the Active grade 

DOUDEN, W. L. KNIGHT, J. B., JR. 

2011 Poplar St., U. S. Navy Underwater Sound Lab., 

Philadelphia, Pa. Fort Trumbull, 

New London, Conn. 

O'GRADY, F. T. 

33-64, 164th St., 

Flushing, L. I., N. Y. 

The following applicant was admitted to the Student Membership grade : 

WHITMER, MARVIN 
417 Marion St., 
Boone, Iowa 



817 



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SOCIETY SUPPLIES 

The following are available from the General Office of the Society, at the prices 
noted. Orders should be accompanied by remittances. 

Aims and Accomplishments. An index of the Transactions from October, 
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JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

VOLUME XXXIX DECEMBER, 1942 



CONTENTS 

PAGE 

The Navy's Utilization of Film for Training Purposes 

W. EXTON, JR. 333 
The Underground Motion Picture Industry in China 

T. Y. Lo 341 
Wright Field Training Film Production Laboratory 

H. C. BRECHA 348 
The Documentary, Scientific, and Military Films of the 

Soviet Union " G. I. IRSKY 353 

A One-Ray System for Designing Spherical Condensers 

L. T. SACHTLEBEN 358 

Light-Scattering and the Graininess of Photographic 

Emulsions A. GOETZ AND F. W. BROWN 375 

Some Engineering Aspects of Portable Television 
Pick-Ups H. R. LUBCKE 

Current Literature 

The 1942 Fall Meeting of the Society at New York, 
October 27-29, 1942 

Program of the Meeting 
Highlights of the Meeting 
Society Announcements 

Index of the Journal, Vol. XXXIX (June- December, 
1942) 

Author Index 

Classified Index ! |1( ' 

(The Society is not responsible for statements of authors,) 



JOURNAL OF THE SOCIETY OF 
MOTION PICTURE ENGINEERS 

SYLVAN HARRIS, EDITOR 

Board of Editors 

ARTHUR C. DOWNES, Chairman 

JOHN I. CRABTREE ALFRED N. GOLDSMITH EDWARD W. KELLOGG 

CLYDE R. KEITH ALAN M. GUNDELFINGER CARLETON R. SAWYER 

ARTHUR C. HARDY 

Officers of the Society 

*President: EMERY HUSE, 

6706 Santa Monica Blvd., Hollywood, Calif. 
*Past-President: E. ALLAN WILLIFORD, 

30 E. 42nd St., New York, N. Y. 
*Executive Vice-President: HERBERT GRIFFIN, 

90 Gold St.. New York, N. Y. 
^Engineering Vice-President: DONALD E. HYNDMAN, 

350 Madison Ave., New York, N. Y. 
^Editorial Vice-President: ARTHUR C. DOWNES, 

Box 6087, Cleveland, Ohio. 
**Financial Vice-President: ARTHUR S. DICKINSON, 

28 W. 44th St., New York, N. Y. 
^Convention Vice-President: WILLIAM C. KUNZMANN, 

Box 6087, Cleveland, Ohio. 
^Secretary: PAUL J. LARSEN, 

1401 Sheridan St., N. W., Washington, D. C. 
* Treasurer: GEORGE FRIEDL, JR., 

90 Gold St., New York, N. Y. 

Governors 

*MAX C. BATSEL, 501 N. LaSalle St., Indianapolis, Ind. 
**FRANK E. CARLSON, Nela Park, Cleveland, Ohio. 

*JOHN G. FRAYNE, 6601 Romaine St., Hollywood, Calif. 

*ALFRED N. GOLDSMITH, 580 Fifth Ave., New York, N. Y. 
**EDWARD M. HONAN, 6601 Romaine St., Hollywood, Calif. 

*I. JACOBSEN, 177 N. State St., Chicago, 111. 
**JOHN A. MAURER, 117 E. 24th St., New York, N. Y. 

*LOREN L. RYDER, 5451 Marathon St., Hollywood, Calif. 

* Term expires December 31, 1942. 
** Term expires December 31, 1943. 



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copies of 15 per cent is allowed to accredited agencies. Order from the Society of Motion 
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York, N. Y. 

Published monthly at Easton, Pa., by the Society of Motion Picture Engineers. 

Publication Office, 20th & Northampton Sts., Easton, Pa. 

General and Editorial Office, Hotel Pennsylvania, New York, N. Y. 

Entered as second-class matter January 15, 1930, at the Post Office at Easton, 

Pa., under the Act of March 3, 1879. Copyrighted, 1942, by the Society of Motion 

Picture Engineers, Inc. 



THE NAVY'S UTILIZATION OF FILM FOR TRAINING 
PURPOSES* 



WILLIAM EXXON, JR** 



Summary. The use of training films automatically achieves standardization of 
instruction, and helps to take the place of many men, formerly instructors, who are 
now needed at sea. 

The production of such training films requires thorough understanding of the 
subject matter of the films, and its application in practice. Furthermore, one must be 
acquainted with the kind of men to be taught by the films and the facilities available 
for teaching them. 

The development and use of such films in the Navy has advanced greatly during the 
past six months, and has covered a vast variety of subjects. 



When I had the pleasure of addressing this organization in Holly- 
wood last May, I told you something of the part that the motion 
picture was beginning to play in the training of men for the navy. 
The situation at that time was briefly this : The navy was, and still 
is, faced with an enormous expansion program, requiring that hun- 
dreds of thousands of men be converted almost overnight from land- 
lubber civilians to man-o-war's men, mechanics, and technicians, for 
our rapidly growing fleet, air arm, and other naval activities. A 
large proportion of these men had to be given special skills so that 
they can handle the complicated and exacting apparatus and equip- 
ment of our modern ships and planes. 

All this training must be done when the number of officers and 
skilled men who are available for instruction purposes is reduced to 
an absolute minimum by the needs of our fleet for all possible skilled 
personnel. Further, all this instruction must be carried out as 
hundreds of separate, individual activities, with consequent danger 
that the differences in the teaching at each activity may result in 

* Presented at the 1942 Fall Meeting at New York, N. Y.; received October 
27, 1942. 

** Lt., U.SJST.R., Bureau of Navigation, Navy Dept.. Washington. D. C. 

333 



334 W. EXTON, JR. Lf. s. M. P. E. 

considerable lack of efficiency when the men are assembled for duty 
at sea. Adding to these difficulties is the fact that modern war, 
being almost entirely technological, involves changes and develop- 
ments in techniques to such an extent that an instructor who may be 
fully up to date at any given moment is likely to be behind the times 
shortly thereafter. 

The motion picture training film, under these circumstances, offers 
many of the essential advantages required to solve these problems. 
The films can be produced under the supervision of experts in each 
subject, so that the highest and most recent standard of information 
is included in each film. The use of the same films at all activities 
concerned automatically effects standardization of instruction. 
Furthermore, to the extent that these films supplement personal in- 
struction, they take the place of many valuable men, at present 
instructing, who are required at sea; and the films should thus 
provide a necessary supplementation for the teaching staff that is 
available. The training films could be utilized also to keep all tech- 
niques up to date, and to correct or adjust techniques as changes are 
made through experience and development. 

You will note that we are concerned with a training program that 
was and still is an emergency rather than a routine program ; and that 
the training film offers special advantages in the overcoming of the 
adverse factors of this great emergency. 

The last time I spoke to you there was a great deal of excellent 
work already being done in the use of motion pictures for training 
purposes. At the beginning comparatively few films had been pro- 
duced specifically for naval training purposes, and comparatively 
few training activities had become habituated to the use of motion 
pictures for training purposes and accustomed to using films in their 
training. 

It is nearly six months since that time. The development and use 
of motion pictures for training purposes in the navy has advanced 
mightily during these past six months. I spent a part of this time at 
sea aboard a destroyer and was myself surprised at the advances 
made, even though I had participated in planning many of them. 
Many more films have become available for training purposes. 
Many training activities, and many officers concerned with training, 
have become aware of the possibilities in the use of training films and 
have adapted them to their purposes and needs. I am informed 
that we now distribute about 2000 separate titles, to more than one 



Dec., 1942] NAVY TRAINING FlLMS 335 

thousand activities. It is the rule rather than the exception today 
that officers given command of ships, not yet in commission, are 
urgently requesting that they be provided as soon as possible with tin- 
training films and projectors with which to prepare their crews i'..i 
the duties to come. The medium of the motion picture training 
film has thoroughly sold itself and is well established in its usage in 
the navy. 

Thousands of people are now familiar with the application of motion 
pictures for training or educational purposes who never dreamed of 
this until the war brought it into general use. You will recall that I 
predicted last May that the educational functions of motion pictures 
would some day exceed in importance and value their entertainment 
function. I can reiterate that prediction today with a great deal of 
support; for outstanding educators have said to me earnestly and 
with an intensity approximating that of the ancient mariner, that the 
Navy's development of training films will have repercussions in 
civilian life after the war that no one today can estimate. 

Responsible and leading educators predict that the introduction of 
the motion picture to the extent now achieved will undoubtedly have 
a profound effect upon education in the future. The Navy is in- 
terested, of course, only in developing motion pictures for its own 
special purposes. The fact that such a development may, however, 
have its influence upon other developments for other purposes can 
not be denied, and it is not unfitting that this should be examined 
at this time. 

Some of you may recall that I took considerable pains to point out 
that the use of the motion picture for training purposes had in com- 
mon with the use of the motion picture for entertainment purposes 
only the fact that both are made with cameras, on film ; and are pro- 
jected on screens in the same manner. I am firmly of the opinion 
that the arbitrary introduction into the training film of the para- 
phernalia of the entertainment motion picture such as the use of 
introductory and incidental music and other entertainment devices 
results in distraction and frustrates the purpose of the training film. 
This has all too often been done merely because of habits developed 
in the making of entertainment film, and results in inclusion of 
material that has no proper place in a film intended to impart under- 
standing to persons with a-serious interest in the subject. I labored 
this point at some length because at that time there was very link 
appreciation of the principles expounded. Since that time, I am 



336 W. EXTON, JR. [J. S. M. P. K 

very happy to say, there has been a much wider realization of the 
fact that the training film is a training film and not an entertainment 
film. Where once it was common to see a training film intended to 
teach the workings of a lathe, or riveting machine, for instance, open 
and close with music and have a musical background for the an- 
nouncer's voice, that is now exceptional, and is generally the earmark 
of the newcomer in the field of the training film. It is not that the 
training film scorns the devices of the entertainment film, but rather 
that any such device must be utilized only functionally that is, when 
it is useful for a training purpose, and not merely when it is entertain- 
ing, and therefore distracting. 

The Navy and along with the Navy, the many companies that 
are producing films for us is learning a great deal about the develop- 
ment of this medium for training purposes. One of the important 
developments within the Navy itself is the assignment to the many 
training activities of officers who are specialists in the utilization of 
motion pictures. These experts in visual aids guide instructors so 
that they may get the best results from the use of the many visual 
aids increasingly being made available. 

One of the most interesting things about the development of the 
training film and in envisioning the future of this development, is the 
concept of the changing, indeed, the ever rising, standards. There 
are standards for the training film existing today in the minds of 
certain individuals that are considerably higher than any actual 
attainments to date. There are officers of the armed services who 
have spent literally thousands of hours looking at training films 
collected from many different sources. They have seen English, 
German, Russian, Japanese, Canadian, and other training films as 
well as those of our own Armed Forces and many developed by 
educational organizations and by private industry. They have been 
faced with numerous problems involving the development of visual 
aids for specific purposes. They have seen these individual projects 
developed, and they have viewed the final products. They have 
evaluated these products in terms of actual use for the purposes in- 
tended. They have seen many efforts to produce training films made 
by persons who had distinguished themselves in the production of 
motion pictures for entertainment. And they have been able to see 
the obvious shortcomings, for the purposes intended, of many of 
these efforts. They have listened to innumerable ideas, theories, 
and proposals from many sources. As a result of all this there has 



Dec., 1942] NAVY TRAINING FlLMS 337 

been built up a very definite consciousness on the part of many of 
those now connected with the armed services, of what is required in 
a general way and frequently in a specific way, if a film is actually to 
succeed in serving a valuable purpose. In connection with any 
given training problem in the solution of which films are to play a 
part, we have learned the necessity of organizing the material for 
maximum assimilability. We have learned the need of exploring in 
its every aspect the function to be performed by those who are to be 
trained. We have been conscious of the fact that we must often 
provide for the pedagogical effect of repetition not necessarily for 
repetition within the film itself, but the film must sometimes be 
planned so that it can profitably be repeated. No element in it must 
seem to deteriorate on repetition. The successful training film must 
be a very skillful and effective blend of intelligent pedagogy (which 
applies the teaching methods proper to the presentation of the sub- 
ject), of technical knowledge (which insures that the subject-matter 
presented is accurate and effective), and of good production (so that 
the film will do complete justice to both the pedagogical and tech- 
nical elements). 

Generally speaking, in planning a film it is necessary to have a 
pretty fair idea of the subject to be taught. It is just as necessary 
to have a good understanding of the application of that subject to 
the service for which it is intended. Then one must have a knowledge 
of the kind of men who are to be taught, and the facilities that will be 
available for teaching them; that is, the general conditions under 
which the film is to be utilized. On the basis of an appreciation of 
these four factors, it should be possible to plan the production of a 
training film that will be accurate in content; designed to be under- 
stood by the men for whom it is intended; and convey to them in a 
manner justifying the use of the medium, the information that it is 
necessary that they should have. 

The fault in many of the training films that have already been 
produced too often lies in the omission or abuse of one or more of 
these factors. A film may be technically correct but badly pro- 
duced; or its pedagogy may be effective for the more intelligent 
person but poor for those who have not had much education. There 
may be excellent pedagogy but poor technology, or excellent tech- 
nology with poor pedagogy. In a few cases good pedagogy plus 
good technology have been ruined by bad production. In the pro- 
duction of films there are often several elements of production. For 



338 W. EXTON, JR. [J. S. M. P. E. 

instance, many of our training films are composed partly of animation 
and partly straight photography. In some cases the animation is 
excellent but the photography fails in its purpose. In others the 
photography is excellent but the animation does not do all that 
might be expected of it. Sometimes much footage is wasted on a 
sequence that could be handled as well or better by the use of film 
strips. 

The use of the commentator the monologue of explanation is 
extremely common. It is possible that great advances will be made 
in the effective use of the voice of the commentator, and in the tech- 
nique of such comment. There is little appreciation of the part 
this element plays in the total effect. 

The use of acting, of dialogue, for training purposes has, of course, 
been highly developed. When well done and when done with an 
understanding of the purpose, it can be invaluable. There is, how- 
ever, a tendency, especially on the part of those who have made film 
for entertainment, to abuse this element by overemphasis, thus in- 
troducing all sorts of distracting elements. 

When we speak of training films we mean films covering a very 
large variety of subjects and also even of interests. We usually, 
among ourselves, specify the major purpose of the film, indicating 
whether it is a film of purely technical instruction, such as Forming 
Sheet Metal, or whether it is an indoctrinal film intended to provide 
general familiarity with a subject rather than specific knowledge to 
be utilized. It may be specific visual education, such as the many 
films that have been made on identification of ships and planes ; or it 
may be a film that is shown for its general effect, such as some of the 
inspirational short subjects that have been produced for general 
popular distribution. 

The production of each kind of training film involves, of course, 
problems that the other types may not present. Individuals who 
may be eminently fitted to produce a film of one kind may not do 
very well with another. There is a growing tendency for persons 
who are charged with the production of films for technical training 
to attempt to include a psychological or inspirational introduction, 
showing the importance of the job to be learned and its place in the 
total war effort. There is much logic in this; for instance, a man 
who must be instructed in the duties of a lookout should be impressed 
with the importance of his function. However, a person skilled in 
technical presentations may not do as well with the less tangible 



Dec., 1942] NAVY TRAINING FlLMS 339 

subjects, and this is, perhaps, another example of the need for in- 
tegrated collaboration. 

In general it may be said that the production of a training film 
requires a coordination of essential creative elements that is rather 
difficult to attain. It is rarely that all these elements can be found 
in one person. Lacking such an unusual individual, it is necessary 
that these elements be found in several persons, who can cooperate 
effectively and successfully. Lacking such cooperation, the film 
produced will be deficient, and will to a greater or lesser extent fail in 
its purpose. 

One of the most interesting of creative developments occurs in the 
kind of cooperation that various individuals have been giving one 
another in the production of training films. As this type of co- 
operation is developed and as those who are outstandingly capable 
of contributing certain essential elements come more and more to 
realize the necessity for simultaneous contribution by other persons 
in the interests of achieving best ultimate results, we may look for- 
ward to the realization of many of the standards now merely visual- 
ized. The realization of these standards will constitute the blazing 
of a trail which should have an invaluable effect upon the production 
of training and educational films for civilian purposes. In addition, 
many films being produced for the Armed Forces have application 
to civilian purposes, and plans are afoot to make such of them avail- 
able as need not be withheld for reasons of security. As these films 
come to be widely shown, it is likely that they will have the effect of 
stimulating civilian demand for the production of such films. 

The many commercial producers now working with the Navy will 
have had invaluable experience that may enable some of them to 
help fill this demand satisfactorily. There is no question in my mind 
that we are actually dealing with the early stages of development of 
an educational medium that will truly revolutionize life. When 
every crossroads school can have the benefit of the direct application 
of educational materials and methods, and even actual instruction 
created by the best qualified talent instead of relying entirely upon 
the local teacher, there will undoubtedly be effected a change in 
the effectiveness of education, the results of which can not be 
foreseen. 

It is possible and even probable that the educational film will be 
used to condition children in early life to conduct themselves aim mi; 
their fellows and their elders in such a way as to pmlisposr t IK-HI for 



340 W. EXXON, JR. 

successful and effective living in the kind of democracy whose future 
we are defending. 

The technology of the motion picture, the engineering aspects, the 
physics, chemistry, and even the economics of the motion picture, 
are already well advanced. The motion picture has been able to 
dominate the field of entertainment, a universal and important field 
previously reserved for a comparatively few talented individuals as 
to performance, and for a comparatively few urban centers as to en- 
joyment. But the application of the motion picture to the inculca- 
tion and dissemination of ideas and to the imparting of specific knowl- 
edge and techniques is in its early infancy. The Armed Forces 
have, through force of circumstance, the privilege of bringing its 
development to a much higher point than any previously attained. 
Their contribution to the development of this medium may well be 
regarded in the future as one of the important results of the war. 



THE UNDERGROUND MOTION PICTURE INDUSTRY 
IN CHINA* 



T. Y. LO** 



Summary. Motion picture production carries on in China under the most 
hazardous conditions of war. The industry has literally had to go underground. 
As protection against the Japanese bombings the laboratories and editing and storage 
compartments are built in tunnels as deep as thirty feet below the surface. At the 
alarm the equipment and portions of the sets and props are carried into the dugouts. 
Actors and directors go on with their rehearsing, while editors and cutters continue 
with their work to the hum of the approaching raiders. Thus production today in 
valiant China. 



The motion picture industry today in China is carried on in dug- 
outs. The motion picture industry is a modern industry, and bomb- 
proof dugouts are even more modern. But before we look at the 
modern aspect of the Chinese motion picture industry, first let us go 
back two thousand years. 

Those were the days before electric lights. In the market square 
after sundown, someone had put up a screen of white cloth stretched 
across two bamboo poles. Behind it, a bright oil lantern burned, 
throwing its light upon the screen. A crowd began to gather to 
watch the spectacle. Music started, and on the screen shadows 
appeared shadows of puppets, images of scholars, warriors, and 
women. A play was enacted. The puppets were skillfully manipu- 
lated by hand, and because they were made of translucent colored 
material, they looked very lifelike and real. 

That was the ancient Chinese "screen show." Today we may 
well regard such a show as good enough only for children, but in those 
days and for the succeeding centuries up to the beginning of the 
Twentieth, these shadow shows, together with the stage plays, held 



* Presented at the 1942 Fall Meeting at New York, N. Y.; received October 
27, 1942. 

** Deputy Chief, Film Section, Political Department, Military Affairs Commis- 
sion, Government of the Republic of China. 

341 



342 T. Y. Lo [J. S. M. P. E. 

the field of popular entertainment in China. The ancient Chinese 
were very proud of this all-action-dialogue-singing-dancing-music- 
and-color screen show. Two thousand years later, we moderns are 
still struggling with the problems that our forefathers imagined 
were completely solved. 

Now, we take a gigantic leap from 100 B.C. to the first decade of 
the Twentieth Century. The first cinema theater in Shanghai was 
opened by a Spanish showman in 1909. The moving picture novelty 
took China by storm. The Chinese called the shadow show "lantern 
shadows." Now, by substituting an electrical contraption for the 
oil lantern, we introduce the fascinating motion picture. So, in 
the image-suggesting language for which we Chinese are famous, 
we call the modern motion picture the "electric shadows" tien 
ying which is still the Chinese name for present-day motion 
pictures. 

From 1931 to 1936, China was in a period of transition. The 
struggle for independence and for freedom from the shackles that the 
train of unequal treaties since the Opium War had put on the Chinese 
nation was still in progress. But above the horizon, another menace 
was rising. Japan, jealous of China's natural resources and her 
growing unity and power, had decided to carry out her plan of conti- 
nental and world conquest. In 1931, sheliad occupied Manchuria. 
Stimulated by this unwarranted attack, Chinese nationalism rose to 
immense proportions. Reverberations were sounded in the motion 
picture world. Film stories produced in China during that period 
mostly reflected the spirit of the Chinese people, who fought against 
aggression on the one hand, and sought to rebuild the country into a 
new nation on the other. 

Two films stood out during that period The Fisherman's Song, 
directed by Mr. Tsai Chosheng, and The Road to Life, directed by 
Mr. Sun Yu. Both were imbued with the spirit of protest against 
oppression, and everywhere in the country they were greeted with 
rousing welcome. They were shown continuously for two months in 
Shanghai and broke all box-office records both for Chinese and im- 
ported films. 

More and more films have been brought into China, including 
Soviet films. Two schools of critics arose with regard to American 
and Soviet films. One maintained that the Soviet film, with its 
serious theme, treated in a powerful style, is the height of cinematic 
art; while the other argued that since the movies are primarily for 





Dec., 1942] MOTION PICTURE INDUSTRY IN CHINA 343 

entertainment, the American films, with their gaiety, liveliness, and 
forwardness in style, are more universal in appeal. 

Before the advent of the talkies there were about twenty motion 
picture companies in China. With the introduction of the sound 
picture a process of absorption and amalgamation began, until 
finally only five held the field, with a number of independent pro- 
ducers attaching to one or another of these. By 1933, the govern- 
ment had also set up several studios the Central Studio, The 
Educational Film Studio, and the China Film Studio; the last to 
become later the China Motion Picture Corporation. A Visual Edu- 
cation Committee was also organized by the Ministry of Education 
to promote popular education through the medium of the cinema. 

Prior to the outbreak of war in 1937, there were 375 cinema theaters 
in China, mostly concentrated in cities along the coast. This figure 
includes nearly a hundred theaters opened farther inland between 
1936 and 1937, during which period there developed a tendency for 
the cinema to spread to the interior. At the same time, the Visual 
Education Committee of the Ministry of Education began to put the 
16-mm silent films to extensive use. Two hundred IG-mm projection 
units were set up at various places throughout the country. The 
Political Department of the Military Affairs Commission organized 
mobile cinema units, showing films not only to the troops, but to the 
people in the villages and towns where the troops were garrisoned. 

For the production of films, the companies imported foreign-made 
cameras, mostly from the United States, but small machines and 
equipment, such as lighting equipment, rewinders, splicers, and 
printers, were sometimes made in the studio workshops and other 
machine shops. In 1931, a recording machine was invented called 
the tien tung, and later another machine came into use, called the 
chunghua tung. In both, the variable-density system with the glow- 
lamp was used. The whole idea is to make the machine into an 
easily portable one. In 1935, an engineer in the Central Studio com- 
pleted a machine for developing films. Besides these, many factories 
and machine shops in some coastal cities also made amplifiers and 
spare parts for sound projectors. The China Film Studio in Hankow 
built sound stages based on the latest models. It is reported that 
the Japanese have now turned these sound studios into stables. 

Now we pass to the next stage in the history of the Chinese movie 
industry. At the end of 1937 the Chinese Army, having withstood 
for three months the violent onslaught of the Japanese invading 



344 T. Y. Lo 

forces, started to withdraw from Shanghai. With that withdrawal 
began one of the greatest migrations in all history. Slowly but 
steadily, the human stream moved west, first to Nanking, then to 
Wuhu and Hankow. Amidst this great migration were fifteen 
hundred people of the motion picture industry of Shanghai. These 
included producers, scenarists, directors, actors, actresses, technicians, 
and studio hands. 

These people joined the government studios, one of which, the 
China Film Studio, moved to Hankow where it organized film pro- 
duction shock units devoted exclusively to war films. In four months 
these shock units completed eleven features and over forty short 
subjects. Another government studio, the Central Studio, was less 
fortunate. In its hasty withdrawal from Wuhu, which was very 
near Nanking, a large amount of its equipment was lost; so it was 
compelled to travel to Chungking where it could be safe from enemy 
bombings, and settled down for rehabilitation. 

In the fall of 1938, Hankow itself was threatened and the last stage 
of the migration began. Three months before, preparations were 
already underway in the China Film Studio for the removal of all 
equipment to Chungking. Systematically, everything that could 
be carried away was transported up the river Yangtze, either by 
steamer or on barges. It was winter and water was low in the 
Yangtze. Wherever the currents ran too swiftly, the studio staff 
had to go ashore and help the boatmen drag the barges upstream by 
ropes. 

It was in Chungking that the Chinese movie industry entered the 
dugouts. Although we are movie people, we had not gone to the 
length of building this subterranean show simply for the romantic 
ring of its name. It was done of necessity. All the headaches, 
heartaches, and backaches would have been for naught if within the 
hour the savage mass bombings of the brutal Japanese had reduced 
everything to ruins. 

Now let us see this strangely located industry in action. Of 
course, not all the work is done in the dugouts. The sound stages, for 
example, are on the ground surface. But the laboratories, and editing 
and storage compartments are built in the tunnels which in some 
parts reach as far as thirty feet below ground. As soon as an air- 
raid alarm is sounded, things start to move. Studio lights, cameras, 
sound equipment, even portions of studio sets and important "props," 
are carried down into the dugouts. Once there, work is resumed. 




FIG. 1. A "long shot" scene taken from Chinese "Lantern Shadow." 
For the convenience of photographing, the "moving sticks" and "sup- 
porting stick" are not shown. 




FIG. 2. Actors, actresses, and extras studying and rehearsing their 
parts in the tunnel during an air-raid. 





FIG. 3. One of China Film Studio's sound stages located in Hankow 
and designed by Mr. T. Y. Lo in 1936. The Japanese have turned it 
into a stable. 







FIG. 4. Miss Lily Lee (Mrs. T. Y. Lo, standing in center) in Storm 
over the Border. Miss Lee spent a year in Inner Mongolia with a crew to 
get the real background for the picture. 



MOTION PICTURE INDUSTRY IN CHINA :;i : 

Directors confer with scenarists on scripts, actors and actresses study 
and rehearse their parts, editors work at their benches, cutting and 
splicing furiously to the horrible hum of approaching enemy raiders. 

One of our great worries is the possible destruction of stages or 
studio sets by Japanese bombs. The worst problem, however, is the 
destruction of the water mains. The China Film Studio is situated 
at the highest point in Chungking. When electric supply is cut off, 
we can still use our own generators as a makeshift. But when the 
water supply is cut off, as it was in 1939, we are compelled to carry 
water from the river at the foot of the hill up to the studio, and by 
this painful means fill a reservoir made specially for the purpose. 
About two hundred people were needed for this task alone. 

I remember an interesting incident that happened in -June, 1939. 
We were at that time producing a film called The Light of East Asia, 
with a large Japanese cast. These Japanese were originally war 
captives who, after spending two years in the Chinese internment 
camp, became aware of the fact that they had been fooled by the 
Japanese militarists. They sent a petition to the Chinese govern- 
ment for permission to form a "J a P anese Anti-War Federation in 
China." It was some of these Federation members who played in 
this film, The Light of East Asia. 

One day, these Japanese were working on one of our back lots, 
quite a distance away from the studio dugouts. An air raid came. 
In the hurry, an amplifier was forgotten. When that was discovered, 
enemy planes were already above Chungking. One of the Japanese, 
Takahashi by name, volunteered to fetch the amplifier. But before 
he got out of the dugout, bombs fell thick and fast. The blast sent 
Takahashi rolling down the steps at the entrance of the tunnel. 

The amplifier was destroyed after all. The wrecked sets could be 
put up again in two days, but the amplifier was quite another matter. 
Furthermore, we had at that time only one portable recording ma- 
chine. But a resourceful recording engineer confidently told the 
director that he could have everything fixed up for use in two days. 
Promptly on time, he produced his amplifier for the shooting. It 
was made out of the parts of a 7-tube d-c radio receiver. 

There are at present three film studios in Chun^kin^. namely, the 
China Film Studio, the Central Studio, and the Educational Film 
Studio, all under various government departments. The China Film 
Studio has a working staff of 700 people. I ts work is chiefly connected 
with military training. All three studios together produce annually 



346 T. Y. Lo U. S. M. P. E. 

about 20 features and 80 short subjects and training films. For ex- 
ample, there are story films like Good Husband, about military service ; 
Victory Symphony, about the well known victory at Changsha, both 
directed by China's famous- director, Mr. T. S. Shih; Storm over the 
Border played by the writer's wile, Miss Lily Lee, which is her 21st 
picture; and films like Anti-Tank Methods, to show how the civilians 
close to the battle front can play their part to stop the advance of 
Japanese tanks. The production of films is greatly affected by the 
transportation problem, since all film has to be imported from 
America. 

I have mentioned other migrant factories. Naturally, these 
factories devote themselves to the production of arms and other 
needs more directly connected with the war. The making of spare 
parts and small machines for the movie industry is thus handicapped. 
But we can still obtain the cooperation of these factories, which are 
themselves built in the dugouts. For example, they make sprockets 
to supply our mobile units and lights for use in the studios. In 1940, 
one of the arms factories made for the China Film Studio a five-plane 
cartoon photographing machine. In a dugout of the China Film 
Studio, there is a repair shop, which also produces tripods and 
camera dollies. An unusual achievement of this repair shop was the 
transformation of an old-model Bell & Howell silent camera into a 
sound camera. The shutter and some gears of the old machine 
were removed but the center axle was retained. The result was a 
purely noiseless sound camera. We are compelled to make all these 
improvisations because to obtain a priority on the supply and trans- 
port of movie equipment from the United States is very much of a 
happy dream. 

The question may be asked as to what we do with the films we 
produce. In Free China, we have 112 theaters as against the pre- 
war figure of 375. These theaters also have their own dugouts to 
store away their projectors during an air raid. Some of them install 
generators to supply the current against a sudden cut-off as a result 
of bombing. The generators use charcoal or vegetable oil for fuel. 
In addition to our own productions, these theaters also show Ameri- 
can and Soviet films. 

Apart from the theaters, the mobile cinema units of the Political 
Department, under the Military Affairs Commission, do some ex- 
cellent work. There are ten of these units, first organized by Mr. 
Y. C. Cheng, of the China Film Studio. Each unit has a captain, 



Dec., 1942] MOTION PICTURE INDUSTRY IN CHINA 347 

two projectionists, two electricians, and four carriers. Sometimes 
they have to tour parts of Free China where there are even no roads. 
They visit villages near the front, showing films to soldiers and 
farmers. The generator alone weighs 150 pounds. Due to the 
shortage of gasoline, alcohol is used. 

According to the report sent in by the captain of one of the units, 
during a period of seven months beginning January, 1940, his unit 
made a journey of three thousand miles from Chungking to Inner 
Mongolia, showing films to audiences totaling one and a half million 
people. They travelled by trucks or on camels. Sometimes they 
could obtain only two mules to carry the generator, so they them- 
selves had to travel on foot. Once, they lost their way in the desert, 
and managed to get out of it only by tracking the trail of another 
caravan. 

But the labor and hardships that these men had to go through were 
duly rewarded. In Inner Mongolia, they showed films to people who 
had never seen motion pictures before, and these people were so 
elated over the fascinating spectacle that they made up a song, set it 
to Mongolian music, and dedicated it to this unit. The song was 
named, Down with the Little Japs. 

Although suffering from a shortage of equipment and raw film, these 
units have done some wonderful work. For instance, the Seventh 
Mobile Unit went right behind the Japanese lines and showed films 
to Chinese people in villages in an area that the Japanese believed 
was under their control. On the wall of the China Film Studio hangs 
a slogan that represents the spirit of these mobile units. It reads as 
follows: Remember One Foot of Film Properly Used Is as Deadly as 
a Bullet Fired against the Enemy. 

This is the simple story of the Chinese motion picture industry of 
the present day. Compared with the great American motion picture 
industry, we are but a toddling infant. We have yet to grow and to 
learn. But we share with you the belief that the motion picture is a 
very effective educational and cultural force. More than that, it is 
an indispensable means of promoting international understanding 
and good- will. 

Today, our one great concern is to win this war. Let us never 
forget that in the motion picture the United Nations have a powerful 
weapon that will make a vital contribution toward a glorious victory 
for justice and democracy. 



WRIGHT FIELD TRAINING FILM PRODUCTION 
LABORATORY* 



H. C. BRECHA* 



Summary. The Army must train more than 2,000,000 men for the world's air 
fronts as quickly as possible. This requires, in addition to instructors, a streamlined 
program of visual education by means of training films. The Wright Field Training 
Film Laboratory is a most modern establishment, and is manned by the most capable 
and experienced producers, writers, directors, and technicians. 

Some of the features described are the portable sound-truck, animation, special 
effects facilities, the film processing plant, and some of the equipment used at the Field. 

The U. S. Army Air Forces must train more than two million men 
for the air fronts of the world, as soon as possible. These men will 
not all be pilots there will be bombardiers, gunners, radiomen, 
navigators, and observers and vitally important the maintenance 
crews: mechanics, armorers, radio repairmen, on all of whom the 
Air Forces depend to "Keep 'Em Flying." 

To prepare this tremendous and diverse body of men requires more 
than instructors, more than the standard teaching aids now em- 
ployed. It requires a new and completely streamlined program of 
visual education which can be accomplished only through the power- 
ful medium of motion pictures. 

And that's where training films come in. By closely coordinating 
its program with the courses taught at the various Air Forces Schools, 
the Signal Corps Training Film Laboratory at Wright Field is pro- 
viding training films that have cut weeks from current courses, at a 
time when every minute counts. 

Of -course, this is not an overnight development. Long before 
most of the United States was aware we might be drawn into war, 
the Army Air Forces and Signal Corps planned and created a Train- 
ing Film Production Laboratory at Wright Field to streamline and 
standardize visual education for aviation personnel. The Signal 

* Presented at the 1942 Fall Meeting at New York, N. Y.; received October 
27, 1942. 

** Wright Field, Dayton, Ohio. 

348 



WRIGHT FIELD LABORATORY 349 

Corps assigned an outstanding motion picture expert, Colonel Freder- 
ick W. Hoorn, to do the job. Colonel Hoorn, who came to Wright 
Field in 1939 with one civilian assistant, now heads a laboratory 
consisting of several hundred persons, including officers and civilians. 

These people are putting forth their extreme effort in expediting 
the production of these training films, thus enabling the Army Air 
Forces, in turn, to speed up their vital training courses. 

Training films require a different technique from the motion pic- 
tures you are accustomed to seeing Saturday night at your favorite 
theater. Instruction not entertainment is sought, and the "star" 
of the training film may be a mechanic or the airport weatherman. 
Tempo of action varies from the careful unscrewing of nuts and bolts 
to the flash of P-40s and Japanese Zeros locked in aerial battle. But 
regardless of the tempo of the picture, every moment of it is planned 
to prepare our pilots and mechanics to do their jobs more thoroughly 
and with greater understanding. Throughout the making of the 
picture, the producers, writers, and directors have the collaboration 
and advice of the "Number One" specialists in the Air Forces. 

Colonel Hoorn has assembled as his staff a capable group of officers 
and civilians who are old hands at making motion pictures. The 
Executive Department, headed by Lt. Colonel H. W. Mixson, assists 
Colonel Hoorn in long-range planning, procurement of personnel and 
administration. 

There are three other major departments that supervise the mak- 
ing of training films the scenario, production, and editing depart- 
ments. 

Director of scenarios is Captain Robert Kissack, whose job is to see 
that the Air Forces' ideas for films are translated into finished work- 
ing scripts. Captain Kissack was formerly head of the department 
of visual education at the University of Minnesota. 

Production Manager is Lt. Hiram Brown, who correlates all phases 
of production and keeps the plant running smoothly. Lt. Brown was 
formerly an executive producer at Republic Pictures. 

The Editorial Department is headed by Major Bertram Kalisch 
who makes it his responsibility to smooth out the picture by effective 
editing. He is also in charge of scoring the narration and synchro- 
nizing it with the picture. Major Kalisch was for many years Assis- 
tant Editor of Paihe News, and News of the Day, and also wrote and 
supervised the production of many theatrical, educational, and 
propaganda shorts. 



350 H. C. BRECHA Lf. s. M. P. E. 

Each of these men is assisted by competent aides who have had 
wide experience in the making of motion pictures. A partial list 
includes Assistant Editor Captain Jack Bradford, formerly with the 
March of Time; and Lt. Richard D. Goldstone, formerly executive 
producer of MGM shorts. 

So much for the executive staff of the organization. Let us look 
over the activities of the skilled craftsmen who direct the pictures, 
make the sets, expose the films, put on the sound-track and perform 
other highly specialized duties. From Hollywood, New York, 
Detroit, Chicago, and even from foreign lands, the Laboratory has 
recruited the best talent available. There are seven producers who 
supervise the various production groups of directors and writers. 

It is the writer's job to translate to teaching film the knowledge 
that the foremost Army Air Force authorities wish to inculcate in 
the thousands of up-and-coming pilots, bombardiers, and other 
aviation students. In order to transfer this knowledge to film most 
effectively, the writer himself must become familiar with the subject. 
He has frequent conferences with the Army Air Force advisers who 
oversee the script throughout its preparation. 

The director who receives the script after it has been approved by 
the proper Army Air Force authorities and by Captain Kissack's 
scenario department prepares to shoot the picture. He often has 
extensive conferences with the writer who can give him invaluable aid. 

The director is perhaps the closest to a training film, because once 
he takes charge of it, it is his responsibility during the rest of its pro- 
duction. He has at his command the services of all the craftsmen 
in the Laboratory. He is responsible more than anyone else for the 
quality. 

Let us take a look at the various departments whose services a 
director often uses. The Camera Department is composed of twelve 
ace cameramen, most of whom are leaders in the field of cinematog- 
raphy. All types and makes of camera are used. B&H, Eyemo, 
and Mitchell cameras are used extensively. As for the lenses, the 
stock is most complete; thus both long and short focus lenses are in 
general use. 

The Sound Department is being built up rapidly, and is provided 
at the present time with three truck channels, a fixed channel, and a 
re-recording channel. New equipment will permit handling five 
sound-tracks simultaneously; e. g., narration, synchronous dialogue, 
music, and two types of sound-effects. Variable-area recording 



Dec., 1942] WRIGHT FIELD LABORATORY 351 

apparatus is used and most of the narration that accompanies the 
pictorial part of the film is non-synchronous. A studio has been set 
up and most of the films being made at the present time are scored here. 

A portable sound-truck goes on location in cases where direct 
sound recording is desired, while a library of sound-effects for dubbing 
purposes is being augmented daily. 

Animation is more than the stuff Donald Duck is made of. At the 
Training Film Production Laboratory, animation drawings are deadly 
serious work. Educators have found that they provide the best 
means of teaching, and they are used by the Laboratory whenever a 
point is to be driven home that can not be shown pictorially. Some 
pictures are nearly one hundred per cent animation. A staff of 80 
animators keeps things moving night and day ! 

Special effects, like animation, is a trick way of getting across a 
point. In the special-effects department at the Training Film Pro- 
duction Laboratory, such dangerous scenes as a forced landing or 
a wrecked oil depot are realistically photographed in miniature with 
a special type of camera. Naturally, this is an old art to Hollywood, 
and so, many of the special-effects staff have been drawn from the 
film capital. Samples of the work of the special-effects staff may be 
found in almost every picture. 

A developing and printing plant has recently been installed. By 
virtue of its completion the Training Film Production Laboratory is 
now entirely self-contained. The new film-processing laboratory 
occupies 2500 sq. ft. of floor space. First tests have proved successful 
and production will go into high gear within the next few days. The 
laboratory is the Army's most modern film-processing unit. 

Designed and installed by Consolidated Film Laboratory's En- 
gineering Department, the machines use variable-speed torque 
motors whose speed varies as the tension on the film increases or 
decreases, as the case may be. A million feet of film per month is a 
possible output, but actual production will be proportional, of course, 
to the varying demand. The new laboratory, which, incidentally, is 
completely sprocketless, is headed by Lt. Ted Hirsch, formerly of 
Consolidated. 

It is a straight-line processing unit in which the exposed film is fed* 
into the developing machine; comes out completely developed, fixed, 
washed, and dried; then goes to the negative breakdown assembly, 
into timing, cleaning and printing, projection inspection; and finally 
into the finishing room for possible additional prints. 



352 H. C. BRECHA 

The completed laboratory will include special rooms for developing 
(wet and dry sections) ; timing ; negative cleaning ; printing ; sensi- 
tometry and control; stock vaults; loading; test projection; 
optical printing; and finishing. Facilities are also provided for 
chemical mixing, circulation, storage, laboratory control, and silver 
reclamation. 

The spirit of the Laboratory something that can not be defined 
easily is high. Cooperation exists throughout the whole structure 
of the organization, and each person likes to feel that he is contribut- 
ing in some small way to victory. 



THE DOCUMENTARY, SCIENTIFIC, AND MILITARY FILMS 
OF THE SOVIET UNION* 



GREGORY L. IRSKY** 

Summary. The documentary, scientific, and military films produced in the 
studios of USSR have one basic, main purpose to show the Soviet people themselves, 
and the rest of the world as well, how the Soviet citizen is living and fighting; how. 
as a result of the war, factories and plants have been established in new localities; 
how the tempo of production has increased; and how the people have contributed and 
sacrificed to hasten the defeat of the enemy. And, despite the exigencies and demands 
of war, cultural, educational, and scientific films continue to be produced in greater 
numbers than before. The war has not hindered or stopped the cultural growth of the 
country. 

As I reported to you at the Hollywood Convention last spring, 
during the war period Soviet Cinematography has been able to re- 
organize its resources to meet the demands of the times. All docu- 
mentary, scientific, and military films that are produced by our 
studios have one basic idea, one main purpose to show not only to 
the Soviet people themselves, but to the whole world, how the 
Soviet citizen is living and fighting ; how the people, at short notice, 
have reestablished their factories and plants in new localities; how 
they have increased their tempo of production; and how they have 
sacrificed themselves in every way to strike blow after blow at the 
bloodthirsty Fascists. These pictures are very valuable in ac- 
quainting the Red Army and the Soviet people with the modern 
technique that is helping us to crush our common enemy. 

Our documentary films and newsreels, which are being released 
regularly, are especially outstanding in this respect the directors 
and cameramen risk their very lives to make these films under the 
fire of battle, working side by side with the soldiers, to give the world 
the true picture of the present war. These films show the terror and 
atrocities brought by the Hitlerite despots. These films show how 

* Presented at the 1942 Falf Meeting at New York, N. Y.; received October 
27, 1942. 

** Cinema Committee of the U.S.S.R., Washington, D. C. 

353 



354 G. L. IRSKY [j. s. M. P. E. 

the Soviet people are heroically and valiantly defending not only the 
liberty of their own country, but that of the entire world as well. 
Despite grave dangers and great difficulties our cameramen film the 
most vivid episodes in the heroic struggles of our Red Army against 
the Hitlerites. Flying with the bombers, they film aerial bombings 
of enemy troops and parachute landings, while on the battlefield they 
film the actual operations of our tank units, infantry, cavalry, and 
artillery. Behind the enemies' lines they find excellent subjects in 
the activities of our people's fearless avengers the guerrillas, both 
men and women. 

A few of our documentary films as, for instance, Our Russian Front, 
Moscow Strikes Back, and others, have already been shown here in 
the United States. Their reception by the American people and the 
American press has been excellent and very gratifying. 

The subject-matter of our documentary films is very diversified, 
portraying the intensity and the strenuousness of our lives. Aside 
from the more recent military aspect of these films, the majority of 
them deal with our industrial achievements and our scientific prog- 
ress. They also reveal the intense research of our laboratories. 
They show the great experiments being conducted in our leading 
factories and on our collective farm fields, where our peasants, using 
modern methods, have successfully surmounted many obstacles and 
are supplying the towns with their products. 

Our Soviet people know only too well how much success on the 
front lines is dependent upon the home front. More than a million 
feet of documentary film has been taken by our cameramen from the 
time the Hitlerite hordes suddenly attacked our country. Years 
will pass, and these historical films will be a permanent record, form- 
ing a perfect tribute to our heroes. They will show our future genera- 
tions how heroically and valiantly their forefathers fought for liberty, 
suffered profoundly, and died nobly to insure the future happiness 
of their children. These films will ever stand as an example of the 
great heroism of the millions of people in the present war, who have 
never faltered or surrendered their right to liberty. These films will 
inspire our future youth also to hold high the banner of liberty and 
independence. 

Let us consider now what we are doing along scientific and edu- 
cational lines. Undoubtedly you all know what great attention we 
give in our young country to the matter of educational films, since 
the law gives every youth the right to an education. We have a 



Dec., 1942] FILMS OF THE SOVIET UNION 355 

great many high schools. We have special technical schools where 
the people can listen to lectures by the various specialists in order to 
improve the quality and increase the quantity of their production. 
We have many institutes, universities, and colleges with students 
representing all the nationalities of the Soviet Union. All the peoples 
of our country start on an equal basis and enjoy equally the inherent 
right to study and pursue their respective studies. 

Before the war, there were approximately 700,000 students en- 
rolled in the country's 800 institutes. Among the 600,000 graduated 
from these institutes are to be found engineers, doctors, teachers, 
leading scientists, artists, architects, design engineers, famous Red 
Army commanders, and leading experts in industries and trans- 
portation. In wartime the Soviet institutes continue their work, 
revising their schedules and programs of study to meet the basic re- 
quirements and demands of the times. By increasing the number of 
study hours in the week and shortening the holiday periods without 
lowering our standards of education, we have been successful in 
accelerating the graduation of students with such favorable results 
that in the year 1941-42 the institutes gave the country 170,000 
trained specialists, which is almost double the number normally 
turned out. The institutes and colleges that have been moved to 
safer localities from the territories temporarily occupied by the 
enemy, continue to function normally. Upon arrival in the new 
towns, professors and students rapidly establish their laboratories 
and classrooms and begin working. Odessa and Kharkov's uni- 
versities are functioning very well in their new homes and the Kiev 
industrial institute now in Tashkent has already graduated 200 
engineers. The above re'sume' shows us that the war has not hindered 
or stopped the progress of the educational and scientific life of our 
country. Therefore, the role of scientific cinematography remains 
on a very high level as a vitally important factor in the training of our 
personnel. 

During the years 1940-42 as many as 450 scientific and educa- 
tional films containing 1559 reels and 1,500,000 feet were made. 
These films cover various subjects, such as geography, history, tech- 
nology, agriculture, and military tactics. In other words, the topics 
or the subject-matter of the films are closely interrelated with those 
studied in the programs of our schools and colleges. 

The Peoples Commissariat of Education has a cinema department 
that has approximately 20,000 16-mm projectors, which are furnished 



356 G. L. IRSKY [j. s. M. p. E. 

for lectures to the high schools upon request. Many of our technical 
and educational films are so effective that they enable us to teach our 
people without the actual presence of a teacher. Under the direction 
of Academician Choudakov, a cinema film entitled The Automobile, 
containing 90 reels, was produced. With the assistance of this film, 
several hundred thousand drivers of cars, trucks, tractors, tanks, 
and motorcycles received instructions in the correct methods of 
driving, and were well trained. 

If some collective farm needs skilled drivers for tractors, this film is 
sent and a group of prospective drivers study the principles of the 
motor and other parts of the tractors and receive the consultations of 
an adviser. After reviewing the film they have actual practice in 
driving. Then they are qualified N to drive. 

When Moscow's famous turner Goudov invented a new method of 
increasing the tempo of production, we made a special film showing 
this method. This gave us the opportunity of utilizing Goudov's 
method in many factories throughout our country. Several pictures 
were made of the great work of our Academician Tsisin in growing a 
new kind of grain for Siberia. This film helped us to explain simply 
to our collective farmers this excellent experiment and, as a result, in 
many barren lands where farmers had never grown any wheat before 
there now appeared a harvest of wheat. 

Pictures were made also for the medical profession and for students, 
medical institutes, and scientists. In the Institute for Medical Re- 
search and Experimentation there was conducted a great experiment 
in the revitalization of organisms. In order to familiarize our 
medical circles with this great experiment, we made a film under the 
title of The Experience in Revitalizing (by Director lashin). This 
film shows how the separate parts of an organism, the heart, for in- 
stance, after having been taken out and put into a special receptacle 
continued to function for a certain period. 

A very good reception was given to a film taken on the sea bottom, 
directed by Mr. Zgurydi. In this film the director and cameraman, 
very completely and entertainingly, show the colorful life on the 
bottom of the sea. For the filming 'of this picture, Soviet engineers 
designed a special camera and cabin in which the cameraman dived to 
the bottom of the water. Very complicated work in the field of film- 
ing scientific biological films was made under the direction of Pro- 
fessor Lebedev, who also designed special equipment for taking pic- 
tures of microbes. 



Dec., 1942] FILMS OF THE SOVIET UNION 357 

In producing scientific and educational films, we have always paid 
particular attention to the military aspect. These training and in- 
structional films have not only helped our fighters to familiarize 
themselves with tactics and the principles of operation of military 
equipment, but also with the methods of proper upkeep and servicing. 

Naturally, the war has required more consideration of the filming of 
military pictures, and in order to meet the demand during recent 
years, our studios have had to make many military films which are 
successfully utilized in our military schools and camps on the battle- 
fronts. In illustration, a few such pictures may be mentioned : 

Hand to Hand Fighting: In this film are shown the methods of hand 
to hand fighting under various conditions. 

The Training of Ski Troops: The Red Army fighters are enabled to 
study quickly the technique of using skis in combat, in reconnaissance 
and marching. 

Defense in Tank Warfare: In this film the director and cameraman 
very successfully depict existing methods of defense against the on- 
slaught of tanks under various conditions in open fields, forests, and 
the like. 

Marksmanship: This film teaches the soldiers and civilians the 
minute details of good marksmanship so that they will at all times be 
ready to defend their native land from the enemy. 

Camouflage in Winter: This film was made on the basis of much 
experience gained when our Red Army fought the Hitlerite invaders 
in the winter time and is a very good subject for training new fighters. 

Mine Control: Emphasizes the caution that must be exercised in 
regard to the mines planted by our enemies and demonstrates the 
modern methods of mine sweeping. 

Training of Parachute Troops: This film shows the jump of the 
parachutist under various conditions and illustrates methods of 
training parachute troops. 

The Anti-Tank Rifle: Shows the principles and action of the anti- 
tank rifle designed by Soviet inventors. This particular rifle has 
had exceptional success in the struggle against Nazi tanks, and the 
film makes possible the training of masses of our fighters. 

The great experience gained in producing documentary and sci- 
entific films will enable us to utilize our resources to the utmost 
advantage in the future for the purposes of reconstruction, further 
progress, and the assurance of a happy life, after we have finally 
crushed the destructive forces of mankind. 



A ONE-RAY SYSTEM FOR DESIGNING SPHERICAL 
CONDENSERS* 



L. T. SACHTLEBEN** 

Summary. A spherical condenser is a simple lens of relatively large aperture. 
The outer portions of such a lens focus the rays much nearer to the lens than do the 
center portions. As a result the lens as a whole fails to produce a sharp image. This 
defect of the lens is known as spherical aberration. 

While in the case of spherical aberration no sharp image is produced, an image- 
like region of best focus does exist. This is- known as the disk of least confusion. Its 
diameter may be minimized by shaping the lens so as to minimize spherical aberration. 
It is with this disk of least confusion and its required location that the designer of a 
spherical condenser must deal. 

Without a knowledge of the properties of the disk of least confusion a designer might 
compute rays through a large number of trial lenses until, by an extensive and costly 
trial-and-error process, a condenser, having the correct shape for minimal spherical 
aberration and the disk of least confusion at the required location, is obtained. 

The present paper examines some simple properties of the disk of least confusion. 
In consequence it shows how, by computing the course of a single ray through the pro- 
posed lens, a spherical condenser will result having the correct shape for minimizing 
spherical aberration, and the correct center thickness for its assumed diameter and edge 
thickness; and for which, finally, the location of the disk of least confusion is known. 
The method is applicable to condensers comprising more than one lens, and leads to 
the required design with a minimum of relatively simple trials. 

Optical condensers are an important part of the motion picture 
engineer's equipment. They are essential in optical systems for the 
recording and reproduction of sound, and only by means of them 
can the motion picture itself be adequately and efficiently illuminated. 
In simplest terms, a condenser is the optical means by which the area 
of a light-source is virtually increased manyfold, in order that a spe- 
cific point or area may be illuminated more strongly than is possible 
with the naked light-source alone. 

Condensers are of various forms and types. The reflecting con- 
denser of ellipsoidal form is widely used in picture projectors; aspheri- 
cal-glass refracting condensers of the parabolic type are used in pic- 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received April 
14, 1942. 

** RCA Manufacturing Co., Indianapolis, Ind. 
358 



ONE-RAY SYSTEM FOR CONDENSERS 359 

ture projectors, and in sound reproducing optical systems. Simpler 
and cheaper, if less efficient, spherical-glass refracting condensers 
are widely used in all types of motion picture equipment employing 
optical condensers, and it is to the problem of their design that at- 
tention is directed in the present paper. The author does not claim 
to have made an exhaustive study of the problem ; the purpose here 
is to indicate the direction in which the solution has been found to lie 
during the course of designing several condenser systems. The sub- 
ject does not seem to have been treated systematically in any pub- 
lished work of which the author is aware, and the problem is worthy 
of considerable further study and elaboration. 

In what follows the author has endeavored to adhere to the sign 
and symbol conventions (see Appendix I) established by Professor 
A. E. Conrady in his treatise on "Applied Optics and Optical De- 




FIG. 1. A simple lens. 

sign." 1 The interested reader is urged to consult that work, if he is 
not already familiar with it, as a practically unfailing aid in the un- 
derstanding and solution of many optical problems. 

INTRODUCTION 

The conjugate axial object and image points, A and B, of the sim- 
ple spherical lens shown in Fig. 1, have their positions related to each 
other by the simple formula 



where /' is the equivalent focal length of the lens, and / and /' are 
measured from the first and second principal planes of the lens, // and 
H' , respectively. This relation holds true for any position of the ob- 
ject point A along the axis, but it is mathematically true only for the 
so-called paraxial rays, which lie infinitely close to the axis of the 
system. In a practical sense it is true for rays inclined as much as 



360 



L. T. SACHTLEBEN 



Q. S. M. P. E. 



2 degrees to the axis or to the incidence normals to the spherical 
surfaces of the lens. 2 (The incidence normal is the normal to the re- 
fracting surface that passes through the point of intersection of the 
ray with the surface.) 

If in Fig. 2 a cone of rays of large angle originating at A and entering 
the lens at height Y z from the axis be considered, it will be found upon 
computing its course through the system that it fails to focus at the 
point B, but comes to focus on the axis at a point somewhat nearer 
the lens, say B z ' ' , at distance L z ' from the second principal plane of 
the lens. The focal error, B Z B = I' L z ', is known as the spherical 
aberration of the lens for the zone of radius Y z , and may be included 
in the above formula, which then becomes 



L.' + B t 'B I f 
for rays at any inclination to the axis. 




FIG. 2. Spherical aberration in a simple lens. 

It is not possible to formulate an exact algebraic expression for the 
spherical aberration in terms of /, Y z , and the radii and refractive in- 
dex of the lens, for the law of refraction is itself trigonometric or 
transcendental in nature. Frequently the spherical aberration is 
expressed as a series in Y z , the constants of which must be evaluated 
for the particular case under consideration. This series takes the form 



B.'B = 

there being no constant term and no odd powers of the variable Y z in 
the expression. 3 The successive terms of the series are said to express 
the primary, secondary, tertiary, etc., spherical aberrations of the 
system. (In general, YI may be any reasonable measure of the aper- 
ture of the lens, and need not be restricted to the height of the point 
of incidence above the axis. In the practical part of this paper Y z will 
be taken as the tangent of the inclination angle U z , between the ray 
and the axis. 3 ) 



Dec., 1942] ONE-RAY SYSTEM FOR CONDENSERS 361 

In view of the above-given statement that the simple lens formula 
holds true, practically, only for rays having inclinations or incidences 
up to 2 degrees, it is obvious that it can not be relied upon when de- 
signing a condenser for which these angles may be as large as 20 
degrees or more. Evidently the presence of spherical aberration must 
be considered. 

THE CONDENSER DESIGN PROBLEM 

It is the function of a condenser ordinarily to direct all the light 
from an illuminated object into a lens that is to project an image of 
the object. Except in certain special cases a condenser is not required 
to be aberration free, but it is usually required to be of quite large 
aperture and frequently must be designed so that the brightest, or 
most concentrated part of the beam emerging from it falls in the plane 
of a lens or other aperture. In general, condensers are simple lenses 
of large aperture required to cover a relatively small field. As such 
they may be studied by considering only the images of object points 
lying on the axis. 

Since a high degree of freedom from spherical aberration is usually 
not one of the conditions of condenser design, it will suffice to assume 
that the actual aberrations of the condenser obey the law of primary 
spherical aberration 

B.'B = a 2 F. 

For simple condensers up to a speed off/2, this equation represents 
the spherical aberration to a sufficiently good approximation if Oi is 
evaluated by computing B Z 'B for an edge or marginal ray, and divid- 
ing that value by the square of the effective semi-aperture of the lens. 

Professor Conrady proves 4 that when the focal errors of a lens 
system obey the law of primary spherical aberration, the best focus 
occurs three-fourths of the way from the focus for the center of the 
lens, to the focus for the edge of the lens. (The proof is corollary to a 
proof 4 that the disk of least confusion occurs "at the point of inter- 
section of the arriving rays from the half -aperture, with the produced 
marginal rays.") This constricted region in the emerging beam of 
light represents the nearest possible approach to a true image in the 
presence of primary spherical aberration, and is known as the disk of 
least confusion. It is with this disk of least confusion, and its location 
on the axis of the system, that the designer of spherical condensers is 
concerned; rather than with the image point B t which exists only for 
rays having inclinations and incidences of 2 degrees or less. 



362 L. T. SACHTLEBEN [j. S; M. p. E. 

FUNDAMENTAL CONDITIONS OF THE SOLUTION 

If the spherical aberration of any zone of the lens of Fig. 2 is ex- 
pressed as 

B.'B = a 2 Y t * 

and the spherical aberration of the margin of the lens as 

B m 'B = 2 F w 2 
then by division 

B *' B _ V2/V 2 

B m 'B ~ Ys/Ym 

Remembering that for the point B zt corresponding to the position 
of the disk of least confusion 



B m 'B 

it is seen that for this point the corresponding Y z is given by 



or 



That is, the zone through which the rays must pass, if they are to 
come to focus at a point B z ' corresponding to the position of the disk 
of least confusion, has an aperture which is V 3 /4 = 0.8660 X the full 
effective aperture of the lens. This zone of the lens, which is thus as- 
sociated with this important point, shall be called the "square-root-of- 
three-fourths-zone" ; written simply as the " v 3 / 4 zone." The deter- 
minate diameter of this zone is the fundamental fact upon which the 
present solution of the condenser problem is based. It is thus clear 
that only the rays from the object-point A that enter the lens at an 
aperture equal to v 3 /^ times the full effective aperture of the first 
surface of the lens need be considered. And since all such rays form 
an axial cone or pencil of rays, which are all refracted exactly alike, 
it becomes necessary to consider only one ray as the key to the solu- 
tion of the problem. 

In Professor Conrady's proof referred to above, it is shown that the 
diameter of the disk of least confusion is proportional both to the 
spherical aberration B m 'B of the rays from the margin of the lens, and 
to the tangent of the angle U m ' which they make with the axis at their 
focus. It is desirable in any condenser system that this diameter shall 



Dec., 1942] ONE-RAY SYSTEM FOR CONDENSERS 363 

be kept as small as conveniently possible, and since both these quan- 
tities vary in the same sense, the diameter of the disk will be smallest 
when the spherical aberration of the marginal ray is smallest. It is 
well known that a simple lens has minimal spherical aberration when 
its shape is such that the change in direction, or deviation of the edge 
ray, is the same at both surfaces. It shall here be prescribed that the 
deviation of the V*7 4 zone ray, rather than the edge ray, shall be 
equally divided between the two surfaces. This will give the lens a 
shape slightly different from that necessary to divide the total devia- 
tion of the edge ray equally between the two surfaces. But since for 
that shape the total deviation of the edge ray is a minimum, the pre- 
scribed small departure from it will change the total deviation of the 
edge ray by a negligible amount. If the condenser is to have four or 
more glass-air surfaces the total deviation of the Vy^ zone ray shall 
be divided equally among all of the surfaces. The component lenses 
will thus all have approximately the same power; they will each have 
very nearly the correct shape for minimal spherical aberration; and 
as will be seen, this equal apportionment of the deviation among the 
surfaces makes it possible to calculate all lens thicknesses, and the 
curvature of every surface after the first, by means of a very simple 
formula. 

SOLUTION OF THE CONDENSER DESIGN PROBLEM 

Having determined the fundamental conditions that the finished 
condenser must fulfill, it is possible to proceed with the actual prob- 
lem of its design. The problem can not well be put into a general 
form, for each design becomes a problem of itself, depending upon the 
particular combination of requirements that must be fulfilled, and 
upon which of the variables are left to be determined by the conven- 
ience of the designer. In general the designer begins with some in- 
formation regarding certain of the following: magnification of the 
system; speed or diameter of the system; distance from system to 
source or image ; separation of source and image ; allowable thickness 
of system ; allowable cost of system ; etc. The problem may thus pre- 
sent itself in innumerable ways. Frequently certain assumptions or 
estimates must be made, and trial designs based upon them until a 
design is found that meets the stated requirements. In such cases the 
assumptions are based upoti actual designing experience. 

The initial inclination of the ray that will traverse the v*/4 zone of 
the lens may be readily calculated from that of the edge ray, which 



364 L. T. SACHTLEBEN fj. S. M. P. E. 

may be known or readily determined from the general requirements 
of the proposed condenser system. Thus, if the initial inclination of 
the edge ray is U m , then the initial inclinaton of the V 3 /4 zone ray is 

U, = tan" 1 v/ 3 ~A tan U m (1} 

Occasionally U z must be estimated, and the design approached 
through a succession of such estimates. 

It is usual for a condenser to be designed to work at some specified 
magnification, say, M, in which case 

sin U t = M sin final U s ' 
or 

final UM' = sin- 1 ^jp (2) 

If M is not given, a trial estimate of it may also be necessary. Thus 
the total deviation of the ray becomes simply 

-U. + final UM' (5) 

If, further, I I' = 6 is the deviation of the ray at each surface, 
and Q is the number of individual lens elements comprising the pro- 
posed condenser, then 

2<2 X 6 = - U, + final U,' 
or 

e = ~ U. +^final U.' (4} 

After choosing the glass from which the condenser is to be made 
(usually some variety of Crown), the initial angle of incidence /, of 
the ray, may be calculated. SnelTs Law of Refraction is expressed 
in terms of the sines of the angles of incidence and refraction, 7 and 
I', respectively, and the corresponding indexes, N and N f , of the first 
and second mediums, thus: 

N sin / = N' sin /' 

But where there are given only the indexes and the deviation / I' = 
6, as in the present case, then from Snell's Law, by Appendix II, 



I = cotan-i -jp\ (5) 




Dec., 1942] ONE-RAY SYSTEM FOR CONDENSERS 365 

Having computed U z , and / by equations 1 and 5 above, it is finally 
necessary to choose the distance LI from the object-point A to the 
first surface of the condenser, if it is not already given; after which 
the radius of curvature r\ of the first surface may be computed by the 
formula, derived in Appendix III 



Following this, the remaining curvatures and thicknesses of the 
system may be rapidly computed by alternate application of the 
standard trigonometric computing formulas 7 ' * 9 (see Appendix IV) 
and a simple algebraic formula to be deduced in Appendix V. (The 
Standard trigonometric computing formulas are a group of simple 
trigonometric equations by which the coordinates of a ray, after re- 
fraction at a spherical surface, are computed from its coordinates be- 
fore refraction.) 

The work is continued by introducing LI, U\ = U n , and TI into the 
standard trigonometric-ray tracing formulas and computing L\ and 
Ui' for the v*/* zone ray in the second medium, after refraction at the 
first surface. This computation automatically yields the angles /i 
and /i', whose difference I\ Ii should be equal to 6 above. For the 
second surface of the lens Lz = L/ di' t where d\ is the center thick- 
ness of the lens (as yet undetermined). 

The assumption of equal deviation of the ray at each surface now 
leads, by Appendix V, to the important algebraic formula relating 
La, and the second radius of curvature r 2 , thus : 

(7) 



L 2 Li' - di' 2ri - V 

From equation 7 it is seen that the ratio of r* to La is a constant which 
may be evaluated in terms of the now known data r\ and L\ for the 
first surface. Equation 7 makes possible a slide-rule computation of 
r z , upon the assumption of any trial value of d\, from which the edge 
thickness of the lens at its assumed or required diameter may be com- 
puted (see Appendix VI). When a value of d\ has been found that 
will yield a satisfactory edge thickness the corresponding value of 
ra is accurately computed. The values of Lj, U\ t and fj are then in- 
troduced into the standard ray-tracing formulas, and the new L' and 
U 2 ' computed trigonometrically for the Vyi zone ray after its refrac- 
tion at the second surface. The difference /t - /t' should again be 
computed and seen to be equal to 0. 



366 L. T. SACHTLEBEN [j. s. M. P. E. 

Equation 7 may now be rewritten with suffixes increased by unity, 



as 



- L 2 f ' va) 

and applied as before to compute the third radius of curvature. This 
is allowable, for the relation expressed by equation 7 is purely geo- 
metrical and unrelated to the laws of optics. Ordinarily, the second 
and third surfaces of the lens are separated by an air-space d 2 ' of 
nominal length, say 0.5 mm. As there can be no question of edge 
thickness at the air-space for lenses of this form, since such spaces 
have negative curvature, it is permissible to assume a nominal thick- 
ness for the air-space and immediately compute r 3 . 




FIG. 3. Form and proportions of a lens designed by the 
one-ray method, showing the course of the \/M zone ray. 

It is now evident that completion of the design of the condenser is 
only a matter of repeating the procedure, outlined above for the 
second and third surfaces of the lens, until all the radii and thick- 
nesses of the originally assumed number of component lenses have 
been computed. 

EXAMPLE 

In Appendix VII, an actual design is carried through in detail, the 
condenser having a speed of about//!, and a magnification of M = 
4.5 X- Fig. 3 illustrates the form and proportions of the resulting 
lens, and shows the course of the V 3 / 4 zone ray through it. 

Fig. 4 illustrates the distribution of the rays in the vicinity of the 
focus. The focus of the V 3 / 4 zone ray is seen to lie very near the disk 
of least confusion, which, due to the presence of the higher-order aber- 
rations, is itself displaced toward the lens from the originally assumed 
theoretical position. The fact that the focus B of Fig. 4, computed 
by the simple lens formula, lies nearly 2 l /t inches beyond the disk 



Dec., 1942] ONE-RAY SYSTEM FOR CONDENSERS 367 

illustrates the futility of using the simple lens formula when designing 
lenses of this type. 

The computations of Appendix VII would normally represent about 
three hours' work, and in actual practice two to four trials may be re- 
quired to produce a condenser fulfilling all the requirements of a de- 
sign. 

APPENDIX 

(I) SIGN AND SYMBOL CONVENTIONS* 

A ray is completely designated with respect to a given spherical refracting sur- 
face if its point of intersection with the chosen axis of that surface and its angle 
of inclination to the axis are given. Professor Conrady chooses to apply the nega- 




FIG. 4. Distribution of rays in the vicinity of the focus 
of the lens of Fig. 3. Computed rays: (a) marginal ray; 
(6) x/Ji zone ray; (c) half -aperture ray; (d) estimated 
ray (not computed). B represents the location of the 
image as computed by the simple lens formula. Vertical 
scale increased 5X for clarity. 

tive sign to all intersection-lengths lying to the left of a surface, and the positive 
sign to all those to the right. The radius of curvature of a surface is treated as the 
intersection-length of any normal to that surface, and is therefore negative 
if the center of curvature lies to the left of the surface, and positive if it lies to the 
right. He chooses to measure the inclination of a ray by the acute angle that the 
ray makes with the axis, calling the angle negative if it is generated by a counter- 
clockwise rotation from the direction of the axis into that of the ray, and positive 
if generated by a clockwise rotation. Accordingly the angles of incidence and re- 
fraction are positive if generated by a clockwise rotation from the direction of the 
ray to the direction of the radius or incidence normal. The axis of a single spheri- 
cal surface may be any straight line through the center of curvature, but in a 
system of two or more spherical refracting surfaces, the centers of curvature of all 
the surfaces are made to lie on the same straight line, which is then regarded as 
their common axis. 

Inclination angles for rays actually in the medium to the left of a refracting sur- 
face are designated by a plain vowel, as U; and in the medium to the right by a 



368 



L. T. SACHTLEBEN 



LT. S. M. P. E. 



primed vowel, as U'. Intersection-lengths for rays actually in the medium to the 
left of a surface are designated by a plain consonant, as L; and in the medium to 
the right by a primed consonant, as L'. In like manner / and I' designate the 
angles of incidence for rays actually in the mediums to left and right of a surface, 
respectively. Capital letters designate the data of rays at finite angles to the 
axis, and small letters the data of rays lying indefinitely close to the axis. 

N and N' designate the indexes of refraction of the mediums to the left and 
right of a surface, respectively; d and d', which are always positive in the usual 
left-to-right computation, designate the axial thicknesses of elements to the left 
and right of a surface, respectively. 

Numerical subscripts refer the above symbols to particular surfaces that are 
numbered successively from left to right, beginning with 1. 

(II) THE ANGLE OF INCIDENCE 
The relation between the angles of incidence and refraction, / and /', and the 




FIG. 5. 



corresponding indexes of refraction, N and N', is known as Snell's Law of Refrac- 
tion and is stated thus: 

N sin / = N' sin /' 
The change hi the direction of the ray or its deviation upon refraction is equal to 

/ - /' = 6 

By transposition and substitution Snell's Law becomes 
N sin / = N' sin (/ - 0) 
Upon expansion of the right hand term 

N sin I = N' (sin / cos 6 cos / sin 0) 
and upon dividing this equation by sin /, and transposing 



= cotan i 



sin0 



Dec., 1942] ONE-RAY SYSTEM FOR CONDENSERS 369 

(in) THE FIRST RADIUS 

Professor Conrady proves' (see Fig. 5) that if a ray at inclination U intersects 
the axis of a spherical surface of radius r at a point B t which is separated a distance 
L from the vertex A of the surface, and meets the surface at an angle of incidence 
/, then the length of the chord connecting the point of incidence P with the vertex 
A may be written 



PA - L sin U sec 



But since also 



then by substitution and transposition 

r = sin U sec -^ 



17 I + U 

cosec 



(6) 




FIG. 6. 



(IV) STANDARD TRIGONOMETRIC COMPUTING FORMULAS' 

If the axial intersection length L, and the inclination 7 of a ray are given, and if 
the refractive indexes N and N' of the first and second mediums, respectively, are 
given, and if, furthermore, the radius of curvature r of the spherical refracting 
surface is known, then the new intersection length L' and new inclination V of 
the ray after refraction may be computed by the following formulas: 1 ' 

The angle of incidence / in the first medium of index N is given by 

sin / = sin 
The angle of incidence /' in the second medium of index N' is given by 

sin /' - p sin / (B) 

The inclination U' of the ray after refraction is given by 

U' - U + / - /' (O 



370 L. T. SACHTLEBEN [j. s. M. P. E. 

The intersection-length L' of the ray after refraction is given by 



Where d' is the axial distance to the next succeeding surface, the new L for that 
surface becomes L' d', and the new U is obviously equal to U'. 

(V) ANY RADIUS AFTER THE FIRST 

Given two spherical surfaces of radii r\ and r 2 , separated a distance d\ (Fig. 6). 
Consider any line PP' which connects the two surfaces, and whose extension 
intersects the axis of the two surfaces in the point A' at a, distance L\ from the 
vertex of the surface of radius r\. In general the line PP' will make an angle I\' 
with the radius CiP of the surface of radius r it and an angle 7 2 with the radius 
CzP' of the surface of radius r 2 . The line PP' will be inclined at an angle /i' = Z7* 
to the axis of the two surfaces. 

From the triangle A'C\P, for the first suface 

7- / 

Li\ T\ T\ 

sin h' = ihTTV 
and from the triangle A'CzP', for the second surface 



= 
sin Iz sin Uz 

By division of the second equation by the first 

Li r 2 sin // _ r 2 sin U\ 
Li r\ sin Iz f\ sin Uz 

By imposing the condition that I\ = Iz and, at the same time, noting that 
Ui r = Uz, and I* = L\ di, there results the simple algebraic equation 



from which 

r JL - r<l ri (7\ 

L 2 L^'-di' 2r l -L 1 ' 

a purely geometrical relationship. 

(VI) RADIUS, SEMICHORD, AND SAGITTA OF AN ARC 

The radius r, semichord d, and sagitta h of the circular arc A CB (Fig. 7) are 
related by the formula 

_ h* + d 2 
~~2h~ 

This may be written as 



Dec., 1942] 



ONE-RAY SYSTEM FOR CONDENSERS 



371 



B 



By allowing h/r to assume an appropriate series of values from to 2, a correspond- 
ing series of values of d/r may be computed, and plotted against h/r as abscissas. 
From this curve d may be readily deter- 
mined when h and r are given, or h may be 
obtained when d and r are given. 

By dividing each member of the series 
of computed values of d/r by the corre- 
sponding values of h/r, a likewise corre- 
sponding series of values of d/h is obtained. 
When these values are plotted against h/r 
as abscissas the resulting curve easily 
yields d when h and r are given, or yields r 
when d and h are given. 

The two curves thus obtained are in- 
valuable in quickly solving problems in- 
volving the center and edge thicknesses, 
radii, and diameters of lenses. They 
quickly repay the trouble spent in comput- 
ing and plotting them. 




p IG 7 



(VII) EXAMPLE 

The lens to be designed will have a speed of about //I, and will work at a mag- 
nification M = 4.5 X. The inclination UM of the edge ray arriving from the 
source will be taken as 25 degrees, and the distance LI from the source to the 
first refracting surface will be taken as 1 inch. It is assumed that the lens will 
be made of glass having an index Ni f = 1.5230. The lens will comprise two ele- 
ments, as the speed of any individual element should not exceed //2. 

By equation 1 



U,(= Ui) = tan~ l 0.866 tan -25 = - 22 (very nearly) 



By equation 2 



Assuming, upon the basis of experience, that the distance L* from the last sur- 
face of the lens to the image will be 5 inches, the estimated diameter of the lens 
is calculated as 

Diameter - i-^ tan 447' - 0.96 inch 

U . oOO 

(It will be convenient to take the diameter as 1 inch, and compute the center 
thicknesses upon an assumed edge thickness of 0.1 inch.) 
By equation 3 

-U, + final U.' - 2647' 

and by equation 4 



2647 / 
2X2 



- 641'45'? - 2 elements) 



log sin / = 


9.51498 


colog N f = 


9.81730 


log sin /' = 


9.33228 


I = 


19-06-24 


/' = 


-12-24-39 



372 L. T. SACHTLEBEN [J. s. M. P. E. 

By equation 5, / is computed as follows 10 ' 11 

log cos e = 9.99703 = log 0.993185 

colog -N' = 9.81730- = log -0.656599 
log (cos 0-^) = 9.52710 = log 0.336586 

colog sin e = 0.93331 
logcotan/ = 0.46041 = log cotan 19-06-24 

(The more convenient method of writing angles as 19-06-24, instead of the usual 
196'24", will be used beyond this point.) 

A check of the last computation is most conveniently made by computing /' 
from Snell's Law. Thus sin /' = sin I/N'. 



log sin 12-24-39 



B = 6-41-45 

It will be well to precede the computation of r\ by tabulation of the relevant 
data as required by equation 6. 

L! = -1 l / z (I - U,) = 20-33-12 

U. = -22-00-00 l /*(I + U.) = -1-26-48 

/ = 19-06-24 

By equation 6, r\ is computed as follows 

log Li = 0.00000- 

colog2 = 9.69897 

log sin U. = 9.57358- 

colog cos V 2 (7 - U,} = 0.02856 

colog sin V 2 (7 + U.) = 1.59780- 

log ri = 0.89891- = log -7.92337 

From the now known values of LI, Ui and r\ a computation 7 by the Standard 
trigonometric computing formulas yields 

Li' = -1.47163, and US = U 2 = -15-18-15 

By equation 7, r z /L 2 is computed as follows (assuming di = 0) 

logn = 0.89891- 
colog (2fi - Li 7 ) = 8.84239- 

logr 2 /L 2 = 9.74130 = log 0.551 188 



Dec., 1942] ONE-RAY SYSTEM FOR CONDENSERS 373 

A few trial values of di' show that an edge thickness of 0.1 inch will result from 
a center thickness d\ 0.230 inch. 

By equation 7, r 2 is computed as 

r 2 = (Li' - <*/) 

log (L,' - di') - 0.23087- (- logL,) 
Iogr 2 /Lj - 9.74130 

Iogr 2 = 9.97217- = log -0.93793 

From the known values of Z, 2 , U t , and r, the standard computing formulas 
yield 

IV = -2.98889, and US = U> = -8-36-32 

The third radius may be immediately computed upon assumption of d\ 
0.020 inch. 

By equation 7, r, is computed as follows 

log (ZV - d 2 ') = 0.47841- (= log Z,) 

Iogr 2 = 9.97217- 
colog (2r 2 - ZV) = 9.95349 

log r 3 = 0.40407 = log 2.53554 

From the known values of 3, U s , and r, the standard computing formulas 
yield 

ZV = -13.7880, and 7 8 ' = C7 4 = -1-54-57 

If, as is advisable, a scale drawing is made as the design progresses, to show the 
course of the ray through the system, it will be apparent that the first element 
must be made about 1.062 inches in diameter and the second element must be 
made about 1.125 inches in diameter to accommodate the edge ray. With this in 
mind, the final radius r 4 may be computed. 

By equation 7a, r 4 /L t is computed as follows (assuming d* = 0) 

Iogr 3 = 0.40407 
colog (2r 8 - Z, 3 ') = 8.72448 

log f 4 = 9.12855 = log 0.134447 
L* 

It is seen that L\ is very much larger than any probable value which d\ may as- 
sume, and that as a result the value of r 4 will be only slightly different from the 
value obtained on the assumption that d\ = 0. With this in mind it is quickly 
found that the edge thickness of the second lens (diameter new value of 1.125 
niches) will be very nearly 0.1 inch when the center thickness is 0.250 inch. 

By equation 7a, r 4 is computed -as 



374 L. T. SACHTLEBEN 

log (V - <V) = 1.14731- (= log Z, 4 ) 
logr 4 /Z, 4 = 9.12855 

Iogr 4 = 0.27586- = log -1.88738 

From the known values of Z, 4 , U 4 , and r 4 the standard computing formulas 
yield 

L/ = 5.52255, and E7 4 ' = 4-46-56 
The height of the point of incidence at the last surface is 

F 4 = r 4 sin (U, + 7 4 ) 12 

The free aperture of the last surface is thus 2F 4 /0.866, and is computed to be 
1.080 inches. 

Thus the lens is specified as follows: 

N' = 1 5230 

n = -7. 923 inches di r = 0.230 inch. Diameter = 1 . 062 inches 

r 2 = -0.938 inch 

d 2 r = 0.020 inch (air-space) 

r a = +2.536 inches d 3 ' = 0.250 inch. Diameter = 1.125 inches 

r 4 = 1.887 inch 

Free aperture of first component = 1.030 inches. 
Free aperture of second component = 1.080 inches. 

REFERENCES' 

1 CONRADY, A. E.: "Applied Optics and Optical Design," Part One, Oxford 
University Press, London (1929). 

2 Ibid., p. 37. 

3 Ibid., p. 101. 

4 Ibid., pp. 120-122. 

6 Ibid., pp. 4-6. 

Ibid., pp. 25-26. 

7 Ibid., pp. 6-18. 

8 MARTIN, L. C. : "An Introduction to Applied Optics," Vol. I, Sir Isaac Pit- 
man and Sons, Ltd., London (1930), pp. 16-20. 

9 HARDY, A. C., AND PERRIN, F. H.: "The Principles of Optics," 1st ed., 
McGraw-Hill Book Co., New York (1932), pp. 34-41. 

10 In optical calculations it is common practice to write the characteristic of a 
logarithm as 9 ( = 10-1), in place of 1, to avoid the use of negative characteristics. 

11 Logarithms of negative natural numbers are followed by a minus ( ) sign. 
The result of a logarithmic computation is positive if an even number of such signs 
is involved, and is negative if an odd number is involved. 

12 CONRADY, A. E. : "Applied Optics and Optical Design," Part One, p. 29. 



LIGHT-SCATTERING AND THE GRAININESS OF 
PHOTOGRAPHIC EMULSIONS* 



A. GOETZ AND F. W. BROWN** 

Summary. The factors upon which the optical scattering power of a photo- 
graphic emulsion depend and the relationship of the former to the graininess are 
investigated by a method that consists in determining the ratio of two average trans- 
parencies (7yr 2 ) of a moving emulsion sample of uniform density with a micro- 
photometric device integrating simultaneously over a large (Ti) and a small (T t ) 
section of the sample. The variation of the scattering power (defined as T\/T^ with 
the density is determined (a) for negative emulsions: the finer grain has the larger 
Ti/Ts; (6) for a positive emulsion directly exposed and printed through various 
types of negative emulsions: Ti/T 2 is independent of the resulting graininess; (c) 
for positive emulsions printed with white and ultraviolet light: T\/T\ is not affected 
by the wavelength of the printing light; (d) for a positive emulsion with varying 
gamma (0.44 to 2.5): no influence upon T\/Ti by gamma is observed. 

(I) INTRODUCTION 

Previously the senior author with his collaborators 1 - 2i 3> 4 has 
published an approach to the absolute determination of the graininess 
of photographic emulsions based upon the statistical distribution of 
the relative transparency fluctuations in terms of the Gaussian 
probability function : 



) f%- 
Jo 



= x) 



The graininess coefficient G has been found to be an accurate and 
universal representation of the graininess realization by the subject i v</ 
optical as well as the sound observer, if certain factors such as the 
"discrimination factor" are considered. 

An instrument has been designed and described 4 which by means 
of an automatic microphotometric analysis of a small area of the 
emulsion, exposed and developed to a known uniform density D 
permits the evaluation of the graininess coefficient G by a relatively 
simple manipulation. This graininess meter has been used for a 

* Presented at the 1942 Spring Meeting at Hollywood, Calif. ; received May 
24, 1942. 

** California Institute of Technology, Pasadena, Calif. 

375 



376 



A. GOETZ AND F. W. BROWN 



LT. S. M. P. E. 



number of years in the research laboratories of a large industrial 
producer of emulsions and a great deal of data have been thus accu- 
mulated, in particular with reference to the variation of G with D. 
The evaluation of this particular function brings forth a factor that 
has a major influence upon the subjective as well as the objective 
realization of the graininess, that is, the light-scattering power 
(Callier effect) of the emulsion. In order to clarify the relationship 
between this effect and other factors contributing to the evaluation 




FIG. 1. Apparatus for measuring scattering in photo- 
graphic emulsions: L t tungsten arc lamp; D, rotating 
shutter with adjustable sectors; E, emulsion sample on 
rotating stage; MI, transparent mirror; C-l, C-2, bound- 
ary layer photocells (Lange) ; S, double-pole double-throw 
switch; G, galvanometer. 



of G, an experimental study of the causes of the light-scattering power 
under the particular conditions under which the graininess of an 
emulsion is measured was undertaken. 



(II) THE METHOD 

The method employed is similar to the optical system in the graini- 
ness meter of Goetz, Gould, and Dember; 1 - 4 it differs only in the 
elimination of mechanical parts not essential to the determination of 
the scattering power. 

Fig. 1 gives a schematic view : The tungsten arc lamp L illuminates 



Dec., 1942] PHOTOGRAPHIC EMULSIONS 377 

through an achromatic condenser of large aperture the emulsion E 
mounted upon the rotary stage of a microscope. The intensity of 
the illumination can be varied by a rotating disk D which carries a 
large number of equal-sized sectors which can be obscured individ- 
ually. The speed of rotation of D was adjusted to be far above the 
mechanical frequency of any of the instruments used hence the 
spectral distribution of the light-source as well as the aperture of the 
incident beam were always constant. 

The rotary stage (not shown in the diagram) upon which the emul- 
sion sample was mounted was driven by motor at 30 rpm, and was 
adjusted so that its center was several millimeters off of the optical 
axis of the condenser and objective. In this manner, the transpar- 
ency was averaged over an annular section of the emulsion and local 
irregularities were avoided. The microscopic objective was a 20X 
apochromat with a numerical aperture of //0.60. Above it the beam 
was split by a clear thin glass plate MI deflecting a fraction of the 
light transmitted through the objective into a horizontal direction 
upon a very sensitive photoelectric layer cell (Lange), C-l. The 
vertical beam projected through the tube M into an ocular (15X 
compensation) and from there through a camera. In the image plane 
a second photoelectric cell C-2 was mounted. The difference be- 
tween the positions of C-l and C-2 effected thus, by scanning, an 
integration of the transmitted light over a large area of the emulsion 
in the former, and over a very small area in the latter cell. The 
ratio of the field diameters was approximately 70:1. 

The photoelectric currents were measured with a mirror galva- 
nometer G (Fig. 1) in alternate connection with each of the photo- 
electric cells through a double-throw switch 5. The intensity of the 
light entering the objective was kept approximately independent of 
the density of the emulsion sample in order to obtain commensurable 
galvanometer readings, i. e., by the adjustment of the sectors on D. 

For the calibration of this instrument first a clear glass plate or 
film base (representative of a "non-scattering" object) was mounted 
upon the stage and the photo currents of the lower and the upper cell 
were determined and expressed as the ratio I\/Ii /o. Obviously 
/o is an instrument factor depending only upon the optical configu- 
ration and the geometry of the device. If a scattering object is 
placed on the stage, a change of the light distribution takes place and 
the ratio ///V = / > 7 is observed. 7// 8 represents thus the 
scattering power of the object in arbitrary units. 



378 



A. GOETZ AND F. W. BROWN 



[J. S. M. P. E. 



The density D of the emulsion samples was measured with a gray 
wedge densitometer (Eastman). 

(HI) RESULTS 

(a) Various Emulsions. Fig. 2 represents a typical variation of 
the scattering power 5 with the density D for two different negative 
emulsions varying largely in grain size (A having rough, D having 
fine grain). The measurements were taken from sensitometric 
strips. The straight line in Fig. 2 indicates an approximately linear 



1.3 




1.0 




SCATTERING RATIO 
NEGATIVE FILM 

OANEO D NEG 



.2 



.6 
DENSITY 



.8 



1.0 



FIG. 2. S-D diagram: variation of scattering ratio I/Io with 
density, for two different negative emulsions (A rough grain, D fine 
grain). 

relationship between ,S and D for D > 0.1. The scattering for a 
given value of D is the larger, the smaller the grain of the emulsion. 

(b) Positive Prints. Fig. 3 represents measurements of the S(D) 
function for a positive emulsion exposed directly and exposed 
(printed) through three different types of negative emulsions. It is 
well known that the graininess of a print is under most conditions 
larger than the graininess of the negative; hence the negative emul- 
sions were chosen to vary considerably as far as their graininess is 
concerned. Some of these positive prints thus showed variations 
seen easily with the unaided eye. The observations nevertheless 
indicated that the scattering power of the prints is within the experi- 
mental error the same as for the directly exposed positive film. This 



Dec., 1942] 



PHOTOGRAPHIC EMULSIONS 



879 



proves that the scattering power is independent of the graininess, i. e. t 
size and the distribution of the statistical fluctuations of the grain. 

(c) Printing Method. It is well known that the wavelength of 
the printing light influences the graininess considerably, ultraviolet 
being considerably more favorable, probably due to its being more 
scattered in the negative emulsion. In order to study the effect of 
this type of printing upon the scattering power of the positive film, 
prints from the rough and fine-grain negative emulsions (shown in 
Fig. 2) were made, once with white and once with ultraviolet light. 



1.4 



1.0 



- 












X 


- 




.^ 


o 

^ 


X * 








<f 


SCATTEF 


RING RATIC 


) 


1 


S^ 




POSITIVE FILM 

OPOSITIVE FILM 
PRINT OF FAST PAN NEC 
CPRINT OF MEO PAN NEC 

PRINT OF SLOW PAN NEC 
1 1 




c 

x< 


\ 

\ 


\ 





8 



1.0 



246 
DENSITY 

FIG. 3. S-Z) diagram: variation of scattering ratio 7//o for the 
same positive emulsion exposed directly and printed through emul- 
sions of various grain sizes. 

The results are plotted in Fig. 4, showing no systematic deviation of 
the scattering power for either the nature of the printing light or the 
graininess of the negative material. 

(d) Dependence upon Gamma. A set of sensitometric strips of 
positive film were exposed and developed within a gamma range 
varying from 0.44 to 2.50 and their scattering power measured at a 
density of approximately D = 0.5. The 5-values were found to be 
identical within the experimental error; *'. ., within 2.5 per cent. 
It can thus be concluded that in spite of the large effect that gamma 
has upon the graininess, it does not influence the scattering power of 
the emulsion. 



380 



A. GOETZ AND F. W. BROWN 



[J. S. M. P. E. 



(IV) DISCUSSION OF RESULTS 

From the results described above, it is evident that the statistical 
fluctuations of the grain configuration in an emulsion, that is, the 
factors that cause the chief limitation in the optical resolving power 
as well as produce the noise level on a sound-track and the discon- 
tinuity of a visually realized photographic image, do not influence the 
scattering power; but that the latter is dependent chiefly upon the 
size of the individual grain, i. e., granularity. Thus neither the 
contrast (gamma) of a negative nor the color of the printing (not the 
illuminating) light-source was found to affect the scattering power of 
the positive print within the density range studied. 



1.5 



~L4 



< 
gU 



1.0 



SCATTERING RATIO 
POSITIVE FILM 

A POS-UV O A POS-W 

CD POS-UV o o POS-W 



.8 



1.0 



1.2 



.2 4 .6 

DENSITY 

FIG. 4. 5-Z> diagram: variation of scattering ratio ///o for the 
same positive emulsion exposed with white and ultraviolet printing 
light through a rough-grain and a fine-grain negative emulsion. 



The fact that the scattering power shows an inverse relationship to 
the grain size is in qualitative agreement with observations of various 
previous observers. 5 - 6 The approximately linear relationship be- 
tween scattering power and density, however, is not only at variance 
with the density dependence of the graininess but also with previously 
published results. Narath 7 observed in the density range between 
and 1 a behavior so widely varying among different emulsions that 
one may suspect secondary influences (such as scattering irregulari- 
ties in the emulsion and the base). As this author does not scan 
the sample, his observations are restricted necessarily to a small area 
of the emulsion, where accidental faults mav influence the results. 



Dec., 1942] 



PHOTOGRAPHIC EMULSIONS 



381 



Though Narath's optical arrangement was considerably different 
from the one used here, it is not plausible to explain the difference of 
the density function by the difference in the optical method. 

The difference between the density functions of the scattering 
power and the graininess seem worthy of a brief discussion : Fig. 5 




FIG. 5. G-D diagram: typical variation of graini- 
ness of two different emulsions with the density, where 
Gi t Gi is based upon relative (&T/T m ) and G\ t G t \ upon 
absolute transparency fluctuations. 



shows the graininess density function of two different emulsions, 4 
measured with the graininess meter, i. e., under optical conditions 
identical with those used for the measurement of the scattering 
power, G\ t 2 are determined from relative transparency fluctuations, 
while G s i, G S 2 are determined from absolute transparency fluctuations, 
both from the same pair of emulsions. A comparison between, e. g., 



382 A. GOETZ AND F. W. BROWN [j. s. M. p. E. 

Figs. 3 and 4, and Fig. 5 shows the obvious difference between the 
scattering power and the graininess. This difference results in a 
peculiar mutual relationship between graininess and scattering power 
when both are realized under optical conditions closely similar to 
those employed for image and sound reproduction. If the graininess 
G is defined in terms of LT/T m , i. e., as relative transparency 
fluctuations, realized by determining the amplitude and frequency of 
fluctuations with constant field brightness (constant transmitted 
light), the scattering effect renders the absolute magnitude of AT", 
depending upon the size of the field to which the (constant) field 
brightness (^> T m ) is adjusted. In a small field such as is scanned by 
the upper cell in Fig. 1, an emulsion with a large scattering power 
requires a large total field brightness while an emulsion of equal 
density but small scattering power needs less light; similarly, if a 
large field, such as the lower cell in Fig. 1, is referred to for the ad- 
justment for the field brightness, an emulsion with a large scattering 
power will register a smaller AT" at the upper cell than a sample 
causing only little scattering. In the first case the scattering power 
will cause the observation of a graininess larger than in the second 
instant, though the grain configuration will be identical. At the 
same field brightness a large field will consequently show less apparent 
graininess for an emulsion with a large than with a small scattering 
power, a small field produces, cet. par., the opposite effect. Certain 
differences in the realization of the graininess of identical emulsions 
on large and small fields, such as in picture and sound projection, are 
likely to be due to this relationship. 

Since the relative influence of both factors, graininess and scatter- 
ing, varies with the density, the resulting effect is predictable only if 
both functions are known for the emulsion in question. 

The authors wish to express their appreciation for considerable 
technical assistance received from Agfa Ansco, Binghampton, and 
Agfa Raw Film Corporation, Los Angeles. 

REFERENCES 

1 GOETZ, A., AND GOULD, W. O. : "The Objective Quantitative Determination 
of the Graininess of Photographic Emulsions," /. Soc. Mot. Pict. Eng., XXIX 
(Nov., 1937), p. 510. 

2 GOULD, W. O., GOETZ, A., AND DEMBER, A. : "An Instrument for the Objec- 
tive and Quantitative Determination of Photographic Graininess," Phys. Rev., 54 
(1938), p. 240. 



Dec., 1942] PHOTOGRAPHIC EMULSIONS 383 

8 GOBTZ, A., GOULD, W. (X, AND DEMBBR, A.: "An Instrument for the Abso- 
lute Measurement of the Graininess of Photographic Emulsions," /. Soc. Mot. 
Pict. Eng., XXXIH (Oct., 1939), p. 469. 

4 GOBTZ, A., GOULD, W. O., AND DEMBER, A.: "The Objective Measurement 
of the. Graininess of Photographic Emulsions," /. Soc. Mot. Pict. Eng., XXXIV 
(March, 1940), p. 279. 

THRBADGOLD, S. D.: Phot. Ind., 72 (1932), p. 348. 

EGGBRT, J., AND KUBSTER, A. : Veroeff. Agfa, m (1933), p. 93 ; IV (1935), p. 
49; H. Brandes, Ibid., IV (1935), p. 57. 

7 NARATH, A.: Kinotcchnik, XVI (1934), pp. 255, 287. 



SOME ENGINEERING ASPECTS OF PORTABLE TELE- 
VISION PICK-UPS* 

HARRY R. LUBCKE** 



Summary. The routine oj portable television programing may be termed "ap- 
plied" television engineering. The preceding is hardly more than a byplay of words, 
but is intended to convey the impression of an engineering technique evolved to put a 
program across regardless of extenuating circumstances. The emphasis is not on 
engineering, but on the program, with engineering as one of the tools used in accom- 
plishing the program. 

The essentials of the technique are set forth. Proper preparation requires constant 
servicing of equipment when the latter and staff are available. A pre-program test 
several hours before program time is essential to consistent performance and allows 
reasonable time for correcting installation or transportation-caused faults . A suitable 
equipment "warm-up" period precedes the program. Service failures during the 
program are usually unpredictable but must be met by prompt diagnosis and repair. 
A thorough knowledge of the many circuits, normal and abnormal operational charac- 
teristics thereof, and the "knack" of finding trouble are requisites of this aspect. 

Experience in the technique eliminates certain difficulties by methodical prepara- 
tion. The television engineering attributes of a program location are tested and re- 
corded prior to the arrival of equipment. Voltmeter, dummy load, photometer, field 
glasses, and photographic camera comprise the preliminary test equipment. 

Significant experiences in televising 140 separate portable programs of the Don Lee 
Television Station, W6XAO, Hollywood, are recited. 

"How many minutes until program time?" "Sorry, we were 
delayed; the space for our truck was filled with locked parked cars." 
"What did you do? It doubled the signal strength!" "Switch over 
to camera No. 1 direct, I've got a fire in master control!" 

Such phrases are a part of portable television broadcasting. The 
emphasis is on the program. The action is applied engineering. 
The goal is an uninterrupted succession of perfect pictures. 

A portable television pick-up staff has somewhat the problem of 
the young parent, of inducing the offspring to perform correctly at 
the proper time. The public never knows what may have occurred 
before program time, nor what happens after it, and it cares less. 

* Presented at the 1942 Spring Meeting at Hollywood, Calif.; received April 
15, 1942. 

** Don Lee Broadcasting System, Hollywood, Calif. 
384 



PORTABLE TELEVISION PICK-UPS 



886 



All activities are directed toward establishing the best insurance 
designed to accomplish peak technical performance during the pro- 
gram period. 

Several factors contribute to the desired end: methodical prepara- 
tion, adequate time for preparation, careful testing, an experienced 
crew having the "feel" of the equipment, technical-programing 




FIG. 1. The Mt. Lee television installation 
of the Don Lee Broadcasting System, Hollywood. 
This is the receiving location for all portable 
pick-ups where the incoming image on 324 mega- 
cycles is rebroadcast by station W6XAO. The 
tower is 2000 feet above sea level and the build- 
ing houses all television operations. 



coordination, adequate policing to prevent damage to equipment 
during the program, and "luck." These factors will be treated in 
turn. 

The basis of methodical preparation lies in the formulation and 
use of suitable lists and forms. At the start of our portable pick-up 
endeavors a list of necessary items was formulated, down to pieces 
of rope, masking tape, screws, nails, and a hammer. Upon starting 
on a job, the equipment is checked off against the list. Experience 



386 H. R. LUBCKE [J. S. M. P. E. 

dictates changes, and the lists are frequently revised. Large metal 
tool cases have been found convenient to carry parts, tools, and 
lenses; one case for each classification. 

The principal form employed has been our "Mobile Television 
Pick-Up Work Sheet," which tabulates the information required 
for the pick-up. It is desirable to describe the television require- 
ments to the manager and his electrician on the premises where the 
event occurs. The head of the portable television department 
surveys the site, getting the major portion of the information for 
the form by inspection and by asking questions. 

Many questions are answered in consultation at the site. How- 
ever, as regards important technical factors, the criterion of not 
taking anything for granted unearths difficulties at an early date 
when they are relatively harmless. Thus, the television engineer 
may include two heavy-current electric heaters and an a-c voltmeter 
among his equipment. Placing them on the line removes all doubts 
as to the regulation of the voltage and the ability of the fuses to 
carry the thirty-ampere load. Should this test not be performed 
at this time, it is then performed at the preliminary or propagation 
test, or finally, at the very start of operations as many hours before 
program time as possible. 

Equipment always carried by the survey engineer comprises a 
photometer (or Weston brightness meter), field-glasses, and a photo- 
graphic camera. The former is used to test the installed illumination, 
as at a prize fighting ring, or the effect of grandstand shadows. The 
field-glasses are used to determine whether a line-of-sight path exists 
from the program site to the home television station. Beam tele- 
vision transmitting and receiving equipment operating on a fre- 
quency of 324 megacycles, as used by the Don Lee Broadcasting 
System, requires substantially a line-of-sight transmission path. 
The camera is used to take photographs of the premises pertinent 
to the scene of action, the proposed points of installation, and as an 
additional check on the illumination of the scene. It is not difficult 
to calibrate a given film and camera to the sensitivity of the television 
system, and the photographs thus obtained are a definite guide and 
aid in evaluating existing conditions and in suggesting changes. 

After the initial survey, which may be a week or even a month in 
advance of a new program or series of programs, "adequate time for 
preparation" and "careful testing" call for a propagation test if the 
relay distance is greater than five miles. This entails installing 



Dec., 1942] PORTABLE TELEVISION PlCK-UPS 387 

the portable transmitter and an antenna at the program site and 
sending a "dummy picture" back to the home station. The latter 
is comprised of a group of vertical black and white bars, and is 
produced by a small self-contained portable oscillator operating on 
a frequency of 94,500 cycles. Six white and six black bars are 
produced. By noting the evenness of the boundary from black 
to white the amount of "noise" on the relay propagation channel 
Is indicated. Unevenness is caused by interference bursts occur- 
ring near the time of the high-frequency synchronizing pulse of 
sufficient amplitude to desynchronize the receiver scanning os- 
cillator. 

With relay equipment of given power and sensitivity the only 
method of increasing the signal-to-noise ratio on a pick-up is to vary 
the placement and the type of transmitting and receiving antennae. 
The rapidity and effectiveness with which a desirable combination 
can be effected may be regarded as half the requisite skill of portable 
pick-up work. 

After a few years' work, an organization usually comes to rely 
upon a few types of antennae. In the Don Lee organization these 
have reduced to a "pitchfork" type for transmitting and either a 
pitchfork or F-antenna for receiving. The merit of the former lies 
in portability, ease of erection, and signal-strength performance, 
while the merit of the latter lies in extreme sensitivity or gain. A 
pitchfork antenna consists of sixteen half-wave elements arranged in 
four groups spaced vertically one-half wavelength and horizontally 
one-fourth wavelength. Eight elements are driven, and eight ele- 
ments form parasitic reflectors spaced one-fourth wavelength away. 
A F-antenna consists of two wires ten wavelengths long forming 
a V with a central angle of 30 degrees and the open ends terminated 
in a small inductance, a 50-ohm resistor, and a vertical half-wave 
element "ground," while the closed end comprises a 300-ohm, two- 
wire transmission line which conveys energy to the receiver. 

As important as the antenna itself is its placement in space. I 
am impelled to mention an experience recently related to me, of the 
National Broadcasting Company with the Empire State Building 
installation. This experience emphasizes the importance of antenna 
placement and also shows that the problems and technique of this 
work are not unique to one organization, but are common to all in 
the field. 

A pre-program test was in progress at the New York station with 



388 H. R. LUBCKE tf. S. M. P. E. 

not too encouraging results. The signal-to-noise ratio was not as 
high as desirable. Suddenly it doubled for apparently no reason 
whatever. Investigation soon revealed that a routine window washer 
had just raised the window frame on which was attached the ultra- 
high-frequency receiving antenna, raising it vertically about three 
feet! The effect of this increment in relation to the 1200-ft antenna 
height requires little further comment on the importance of antenna 
placement. 

The experience of the Don Lee organization has shown that in- 
creased elevation of antennae, even above purely wooden roofs, 
invariably increases the signal-to-noise ratio. Roughly, considering 
the placement of the transmitting antenna particularly, and in the 
range of from ten to fifty feet above a building structure, doubling 
the height of the antenna above the structure will double the signal- 
to-noise ratio. This holds whether the propagation path is line-of- 
sight or not, whether there is a clear sweep in front of the building 
toward the receiving station, and whether the building is ten or a 
hundred feet high. 

It is important to note that this occurs in spite of the reverse 
effect of increased feeder loss with increased length. The above 
statements include this countereffect, which latter may double for 
each doubling of height if the transmitter is located at the base of 
the antenna mast. This performance is all the more surprising when 
it is recalled that feeder losses at 324 megacycles are large. We 
invariably use a two-inch-spaced number-twelve two-wire feeder, 
Victron insulated. 

Horizontal positions are equally important. The antenna is kept 
as far as possible from all objects, metallic or non-metallic, but the 
combined effect of several objects in the neighborhood can not be 
known until experimentally determined. Proper technique requires 
that all reasonable displacements be made during the propagation- 
test period. 

F-antennae must be oriented to the transmitter in order to achieve 
maximum response, and besides properly locating the antenna in 
azimuth the vertical clearance above ground and the geometry of 
the V must be adjusted. The vertical angle of maximum receptivity 
decreases with vertical clearance. Particularly when the receiving 
location is a few thousand feet above the program location on the 
plain below, as at Mt. Lee, Hollywood, the V must be at least five 
wavelengths above ground. Alteration of the central angle of the V 



Dec., 1942] PORTABLE TELEVISION PlCK-UPS 

three degrees either side of the theoretical often results in reasonable 
signal increases, thereby compensating for some local idiosyncrasy. 

The last phase, allowing adequate time for preparation, is con- 
cerned with the day of the telecast. Circumstances permitting, tin- 
portable crew is dispatched eight working hours before the scheduled 
conclusion of the telecast. A crew of two engineers and an assistant 
are then able to drive the equipment truck to the location, establish 
necessary connections, place the cameras in position, install sound 
equipment, and make a complete test of facilities two to four hours 
before program time on a pick-up of fixed format, such as a baseball 
game or a boxing or wrestling match. 

On more involved pick-ups, such as a soap-box derby, held in the 
hills and necessitating a portable gasoline-driven power truck, antenna 
erected in a field, cameras established on hillsides, telephone lines 
extended, and conditions of self-sufficiency met as would become a 
military expedition, a crew of six men dispatched ten hours before 
conclusion of the program is required. 

On Easter Sunrise pick-ups from the Hollywood Bowl it has been 
our practice to start installation Saturday afternoon, make tests 
with the failing light of evening, and then with the artificial light 
installed, work until nine o'clock Saturday night and then return at 
four A. M. Sunday morning. Electric heaters are kept on the equip- 
ment all through the night in order to prevent the infiltration of 
dampness, which lengthens the warm-up period considerably. 

On the other hand, we have occasionally televised two portable 
pick-up programs in one day from locations several miles apart, with 
one set of equipment and one crew. With a trained crew of six men 
the equipment can be in operation one hour after arriving at a 
location. 

Careful testing and complete familiarity of the crew with the 
equipment are the best forms of program insurance. Capable port- 
able pick-up television engineers must carefully scrutinize the equip- 
ment performance under all sorts of conditions. The manner in 
which equipment begins and ceases to function upon being switched 
on or off provides a definite indication of any probable surge-provoked 
failure. If a condenser, resistor, or other component fails it does so 
usually during an "on" or "off" operation. The seriousness of a 
failure caused by shutting off the equipment at the end of a success- 
ful pre-program test will be appreciated. Engineers are instructed 
to observe carefully the "die-down" behavior of the equipment; 



390 H. R. LUBCKE 

such as the manner in which the images leave the monitor cathode- 
ray tubes, the rapidity with which transmitter meters return to zero, 
a crackle, a minute spark, and, of course, any odor of burning insula- 
tion. The behavior of properly functioning equipment is invariably 
uniform. Anything unusual is a danger signal. 

In addition, the functioning of the equipment during the pre- 
program test tells an experienced operator whether everything is 
normal, or whether the unusual operation of one or more controls 
indicates a forthcoming failure. An engineer with a keen perception 
of these many operating indications has the "feel" of the equipment. 

Technical-programing coordination is important in preventing 
avoidable disasters. The technical and production heads witness 
a performance, or the sequence and locale of events are described on 
the location by a qualified executive associated with the event. De- 
cisions from artistic and technologic viewpoints are reached, and 
departures therefrom involving general movement of the equipment 
just prior to program time are not allowed. 

Adequate policing is important to prevent damage to the television 
equipment. At one Easter Sunrise service our portable transmitter 
was taken off the air for a few minutes at the close of the program 
by a young man utilizing the power cable as a rope for climbing a 
steep hillside in the Hollywood Bowl. Our operator at the top of the 
hill saw the cable move, engaged in a tug-of-war with the unknown 
climber and a large plug was pulled from its socket in the equipment. 
The next year the cable was firmly tied to a stout stake driven in 
the ground, and a safety loop of cable was interposed between the 
stake and the socket. 

In general, one or more policemen, Boy Scouts, or uniformed 
officials should be detailed to guard the cables and equipment of an 
installation. 

No consideration of portable television operations would be com- 
plete without mention of the unpredictable combinations of circum- 
stances and consequences briefly described as "luck." It is futile 
to attempt to enumerate the countless happenings that occur in 
such operations. The requirements of portability preclude duplicate 
channels of equipment, the vagaries of weather and natural illu- 
mination are factors beyond human control, and the newness of 
television instrumentalities does not provide the reliability to be 
found in other arts and acquired through years of experience. How- 
ever, a conscious alertness of staff tends to minimize the consequences 
of "bad luck" and enhances the opportunities for "good luck." 



CURRENT LITERATURE OF INTEREST TO THE MOTION PICTURE 

ENGINEER 



The editors present for convenient reference a list of articles dealing with subjects 
cognate to motion picture engineering published in a number of selected journals 
Photostatic copies may be obtained from the Library of Congress, Washington, D. C. 
or from the New York Public Library, New York, N. Y. Micro copies of article * 
in magazines that are available may be obtained from the Bibliofilm Service, Depart- 
ment of Agriculture, Washington, D. C., at prevailing rates. 



American Cinematographer 

23 (Nov., 1942), No. 11 
A Portable Developing-Machine for Field Service with the 

Army (pp. 473, 489) 

The First Real Combat Camera (pp. 474-475, 489-490) 
"Post-Recording" Dialog for Educational and Training 

Films (pp. 477, 500) 

A Professional Sunshade for the Eastman Special (pp. 485, 
492) 

British Kinematograph Society, Journal 

5 (Oct., 1942), No. 4 

The Electron Multiplier and Its Application to Sound Re- 
production (pp. 102-110) 

The Post-War Organization of Scientific Films (pp. 111- 

113) 
High-Speed Photography and Its Application to Industrial 

Problems (pp. 114-127) 

Educational Screen 

21 (Oct., 1942), No. 8 

Motion Pictures Not for Theaters (pp. 302-304, 306), 
Pt. 40 

Electronics 

15 (Nov., 1942), No. 11 

Recording Machinery Noise Characteristics (pp. 46-51, 
164-165) 

Motion Picture Herald (Better Theaters Section) 

149 (Oct. 17, 1942), N.> 

How Viewing Angles Determine tin BUMI- Fnrin >f tlu- 
Auditorium (pp. 8-9, 22) 



W. STULL 
W. STULL 

J. A. LARSEN, JR. 
C. MURRAY 



F. J. G. VAN DEN 
BOSCH 

H. D. WALBY 
E. D. EYLBS 



A. E. KROWS 



H. D. BRAILSPORD 



H. SCH I AN.. I K 



392 



CURRENT LITERATURE 



Photographische Industrie 

40 (Jan. 20, 1942), No. 3/4 

Zeitraffung und Zeitdehnung (Time-Lapse and Slow Mo- 
tion) (pp. 22-23) 

40 (Feb. 4, 1942), No. 5/6 
Stereophonic mit Dynamikerweiterung (Stereophonic 

Sound with Wider Dynamic Range) (pp. 34-36) P. HATSCHEK 

40 (Feb. 17, 1942), No. 7/8 

Bin neuer franzosisches Verfahren fur plastische Kino- 
pro jektion (A New French Method for Stereoscopic 
Motion Picture Projection) (p. 47) LUSCHER 

40 (March 3, 1942), No. 9/10 

30 Jahre plastischer Farbentonfilm (30 Years of Stereo- 
scopic Color Sound Film) (pp. 71-72) W. SELLE 

40 (March 31, 1942), No. 13/14 

Die Widerstandsfahigkeit des Film Behalters gegen Feuer 
(Resistance of the Film Container to Fire) (pp. 98-100) 

40 (Apr. 14, 1942), No. 15/16 

Neuzeitliche Lichtgebung in Filmtheatern (Modern Light- 
ing in Motion Picture Theaters) (pp. 108-111) H. WINKLER 

40 (Apr. 28, 1942), No. 17/18 

Neuer Normblattentwurf. DIN ENTWURF 15632 Film 
16-mm Aufnahmespulen (DIN Standard 15632. 16- 
Mm Film Take-Up Spool) (p. 123) 

40 (May 12, 1942), No. 19/20 

Das Auflosungsvermogen bei der photographiscen Auf- 
nahme (The Resolving Power of the Photographic Emul- 
sion). Pt. I (pp. 128-130) 

Optische Kopiermaschine statt Filmtrick (The Optical 
Printer Instead of Film Tricks) (pp. 135-136) 
40 (May 26, 1942), No. 21/22 

Das Auflosungsvermogen bei der photographiscen Auf- 
nahme (The Resolving Power of the Photographic Emul- 
sion). Pt. II (pp. 139-140) 

Filmentwicklungsmaschine ohne Zahntrommeln (Film 
Developing Machine without Sprockets) (pp. 146-148) 

40 (June 9, 1942), No. 23/24 

Kohlenachschub bei H. I. Spiegelbogenlampen (Carbon 
Feeding in High Intensity Reflector Arc Lamps) (pp. 
158-160) 

40 (June 23, 1942), No. 25/26 
GerauscharmerTonfilm (Low Noise Level Sound Film) 

(pp. 170-172) P. HATSCHEK 



H. ROEDER AND 

G. HANSEN 
C. EMMERMAN 



H. ROEDER AND 
G. HANSEN 

W. NAUCK 



PROGRAM OF THE 1942 FALL MEETING* 



OCTOBER 27th-29th, HOTEL PENNSYLVANIA, NEW YORK, N. Y. 

TUESDAY, OCTOBER 27, 1942 

Morning Session: General Session; A. C. Dowries, Chairman 

Report of the Convention Vice-President, W. C. Kunzmann. 

Report of the Financial Vice-President, A. S. Dickinson. 

Report of the Engineering Vice-President, D. E. Hyndnian. 

Welcome by the Past-President, E. Allan Williford. 

Election of Officers and Governors for 1943. 

"Wright Field Training Film Laboratory;" H. C. Brecha, Dayton, Ohio. 

"The Navy's Utilization of Film for Training Purposes;" Wm. Exton, Jr . 
Lt. U.S.N.R., Bureau of Navigation, Navy Department, Washington, D. C. 

"The Documentary, Scientific, and Military Films of the Soviet Union;" Greg- 
ory L. Irsky, Cinema Committee of the U.S.R.R., Washington, D. C. 

"The Underground Motion Picture Industry in China;" T. Y. Lo, Deputy 
Chief, Film Section, Military Affairs Commission, Government 6f the Re- 
public of China. 

Noon: Informal Get-Together Luncheon; E. Allan Williford, Presiding. 

Introduction of Officers-Elect for 1943. 

Addresses by: 

Mr. Claude Lee, Director of Public Relations, Paramount Pictures, Inc., New 
York, N. Y. 

Colonel M. E. Gillette, Commanding Officer, U. S. Army Signal Corps Photo- 
graphic Center, Astoria, L. I., N. Y. 

Colonel Montgomery Schuyler, Assistant Director of Disaster Relief. New 
York Chapter, American Red Cross. 

Afternoon Session: Radio City Music Hall Tour; Sylvan Harris, Chairman. 
An extensive tour of the technical facilities of the Radio City Music Hall. 
front-stage and back-stage; arranged by courtesy of Mr. G. S, Eysscll. 
president and managing director of Radio City Music Hall; Mr. Fred L. 
Lynch, publicity director; and Mr. Harry Braun, sound director. 

Evening Session: Museum of Modern Art Film Library; E. F. Kerns (Technical 
Director, Film Library), Chairman. 

Address on the development of the motion picture by Miss Iris Barry, accom- 
panied by a showing of pictures selected for their importance in the develop- 
ment of the art. 

"Motion Pictures and the War KtTort;" by Captain John G. Bradley. National 
Archives, Washington, D. C. 

* As actually followed at the sessions. 



394 PROGRAM OF THE FALL MEETING [j. s. M. p. E. 

WEDNESDAY, OCTOBER 28, 1942 

Morning Session: General Session; D. E. Hyndman, Chairman. 

"Sound Control in the Theater Comes of Age;" H. Burris-Meyer, Stevens In- 
stitute of Technology, Hoboken, N. J. 

"Recent Developments in Sound-Tracks;" Edward M. Honan and Clyde R. 
Keith, Electrical Research Products Division of Western Electric Co., 
Hollywood, Calif. 

Society Business 

Report of the Theater Engineering Committee; Alfred N. Goldsmith, Chair- 
man. 

"Effect of High Gate Temperatures on 35-Mm Film Projection;" E. K. 
Carver, R. H. Talbot, and H. A. Loomis, Eastman Kodak Co., Rochester, 
N. Y. 

"Film Distortions and Their Effect on Projection Quality;" E. K. Carver, 
R. H. Talbot, and H. A. Loomis, Eastman Kodak Co., Rochester N. Y. 

Afternoon Session: General Session; J. A. Maurer, Chairman. 

"Recent Laboratory Studies of Optical Reduction Printing;" R. O. Drew and 

L. T. Sachtleben, RCA Manufacturing Co., Inc., Indianapolis, Ind. 
"Some Characteristics of Ammonium Thiosulfate Fixing Baths;" Donald B. 

Alnutt, Mallinckrodt Chemical Works, St. Louis, Mo. 
"Copper and Sulfide in Developers;" R. M. Evans, W. T. Hanson, Jr., and 

P. K. Glasoe, Eastman Kodak Co., Rochester, N. Y. 

"Factors Affecting the Accumulation of Iodide in Used Photographic Develop- 
ers;" R. M. Evans, W. T. Hanson, Jr., and P. K. Glasoe, Eastman Kodak 

Co., Rochester, N. Y. 
"Effect of Composition of Processing Solutions on Removal of Silver from 

Photographic Materials;" J. I. Crabtree, G. T. Eaton, and L. E. Muehler, 

Eastman Kodak Co., Rochester, N. Y. 
"A Precision Recording Instrument for Measuring Film Width;" S. C. Coroniti 

and H. S. Baldwin, Agfa Ansco, Binghamton, N. Y. 

Evening Session: Fifty-Second Semi- Annual Banquet and Dance. 
Introduction of Officers-Elect for 1943. 
SMPE Journal Award. 

THURSDAY, OCTOBER 29, 1942 

Morning Session: Symposium on the Production of 16-Mm Motion Pictures; 
Ralph E. Farnham, Chairman. 

Introduction by John A. Maurer, Chairman of the Committee on Non-Theatri- 
cal Equipment. 

"Sixteen-Mm Production Planning;" Russell C. Holslag, J. A. Maurer, Inc., 
New York, N. Y. 

"The Practical Side of Direct 16-Mm Laboratory Work;" Lloyd Thompson, 
The Calvin Co., Kansas City, Mo. 

"Sixteen-Mm Laboratory Practice;" Wm. H. Offenhauser, Jr., Washington, 
D. C. 



Dec.. 1942] PROGRAM OF THE FALL MEETING 395 

Afternoon Session: Symposium on the Production of 16-Mm Motion Picture! 

(Continued); Frank E. Carlson, Chairman. 
"Sixteen-Mm Sound Recording;" John A. Maurer, J. A. Maurer. Inc., New 

York, N. Y. 
"Sixteen-Mm Editing and Photographic Embellishment;" Larry Sherwood. 

The Calvin Co., Kansas City, Mo. 
"Sixteen-Mm Screen Illumination;" Frank E. Carlson, General Electric Co., 

Cleveland, Ohio. 
'^Carbon Arc Projection of 16-Mm Film;" W. C. Kolb, National Carbon Co., 

Cleveland, Ohio. 
"Application and Distribution of 16-Mm Motion Pictures;" F. W. Bright. The 

Aetna Casualty and Surety Co., Hartford, Conn. 
"Improvement in Motion Picture Printer Illumination Efficiency;" C. J. 

Kunz, H. Goldberg, and C. E. Ives, Eastman Kodak Co., Rochester, N. Y. 

Evening Session: U. S. Army Signal Corps Photographic Center; General Ses- 
sion; E. Allan Williford, Chairman. 

Welcome by Colonel M. E. Gillette, Commanding. 

"Analysis of Fast Action by Motion Pictures;" E. M. Watson, Capt., Ord- 
nance Dept., Watervliet Arsenal, Watervliet, N. Y. 

"Sixteen-Mm Motion Pictures and the War EiTort ;" Michael S. David, General 
Motors Corp., Detroit, Mich. 

"Motion Pictures in Aircraft Production;" Norman Matthews, Bell Aircraft 
Co., Buffalo, N. Y. 

Exhibition of Army Training Films produced by the U. S. Army Signal Corps. 
and conducted tour of the Photographic Center, U. S. Signal Corps. 



HIGHLIGHTS OF THE FALL MEETING 

HOTEL PENNSYLVANIA 

NEW YORK 
OCTOBER 27-29, 1942 



The 1942 Fall Meeting of the Society, recently concluded at New York, re- 
flected very strongly the state of the times. The program included seven pres- 
entations dealing directly with the uses and applications of motion pictures in 
the prosecution of the war, and a number of other papers on industrial applica- 
tions of motion pictures in the war industries. 

The sessions were remarkably well attended, as well as the sessions of any 
previous Meeting, far beyond expectations in view of the pressure under which 
the members of the motion picture industry are laboring in these troublous times. 
The interest of the Armed Services of the nation in our semi-annual meetings is 
also very gratifying; the Army, the Navy, and the Air Forces are all represented 
on the program, and an outstanding feature of the three- day conclave was the 
session held at the Photographic Center of the U. S. Army Signal Corps at Astoria, 
Long Island. 

An innovation of the Meeting was the holding of three of the sessions away 
from the Hotel headquarters: one at the Museum of Modern Art Film Library, 
another at the Radio City Music Hall, and the third, as mentioned, at the Army 
Signal Corps Photographic Center. These sessions provided interesting and 
profitable relief from the routine, and sometimes arduous, regular papers sessions. 

After the usual reports of the Officers of the Society, the Tuesday (October 
27th) morning session opened with a description by H. C. Brecha of the new 
Army Air Forces Laboratory at Wright Field and an account of the production of 
training films for the Air Forces. This was followed by a discussion by Lt. Win. 
Exton, Jr., of the Navy's program in the utilization of training films. Of especial 
interest were the papers by Gregory L. Irsky and T. Y. Lo, describing the progress 
of the motion picture industries in the U.S.S.R. and in China under the diffi- 
culties of actual warfare. Motion pictures play an exceedingly important role on 
the Russian front, not only in helping to maintain the morale of the fighting 
forces and the civilian population in the fighting areas, but also in training the 
soldiers actually at the front. In China, Mr. Lo reported, the motion picture 
studios actually had to move from place to place to avoid the Japanese bombings, 
and, in fact, eventually had to construct laboratories and other facilities below 
ground. 

At the informal luncheon held at noon in the Roof Garden of the Hotel Mr. E. 
A. Williford, presiding in the absence of the Mr. Emery Huse, president of the 
Society, announced the results of the elections for 1943. The successful candi- 
dates were as follows: 

President: Herbert Griffin 
Executive Vice-President: Loren L. Ryder 
Editorial Vice-President: Arthur C. Downes 
Convention Vice-President: William C. Kunzmann 
396 



HIGHLIGHTS OF THE FALL MEETING 397 

Secretary: E. Allan Williford 
Treasurer: M. R. Boyer 
Governors: W. A. Mueller 

H. W. Remersheid 

Mr. Emery Huse continues as a member of the Board in the capacity of Past- 
President. Terms of office of those listed above are for two years, except for the 
Secretary and Treasurer, who held office for one year. 

Additional members of the Board of Governors are Dr. Alfred N. Goldsmith, 
who was reflected Chairman of the Atlantic Coast Section, and Charles W. 
Handley, elected Chairman of the Pacific Coast Section. At the business meeting 
of the Society, held on the morning of Wednesday, October 28th, amendments of 
the Constitution and By-Laws were adopted providing for five additional Board 
members. Those appointed to fill the vacancies created by the establishment of 
these new Board members were H. D. Bradbury, J. H. Spray, R. O. Strode, 
A. M. Gundelfinger, and H. W. Moyse. The amendments referred to were pub- 
lished in the September issue of the JOURNAL, p. 208. 

Following the announcements by Mr. Williford, the principal speaker at the 
luncheon was Mr. Claude Lee, Director of Public Relations of Paramount Pic- 
tures, Inc., New York. Seated also at the speakers' table were Col. M. E. 
Gillette of the U. S. Army Signal Corps, and Col. Montgomery Schuyler, Assis- 
tant Director of Disaster Relief of the New York Chapter of the American Red 
Cross. 

In the afternoon the members of the Society were the guests of the Radio City 
Music Hall. Through the courtesy of Mr. G. S. Eyssell, president and managing 
director of the Music Hall, Mr. Fred L. Lynch, publicity director, and Mr. Harry 
Braun, sound director, a special tour of the technical facilities of the Music Hall, 
both front-stage and back-stage, was provided. The tour included practically 
all the departments of the organization concerned with putting on the show: 
projection room, sound department, wardrobe department, power plant, refriger- 
ating plant, stage equipment, music department, etc. The Society extends its 
thanks to Messrs. Eyssell, Lynch, and Braun for this interesting contribution to 
our sessions. 

The evening session of Tuesday was held in the auditorium of the Museum of 
Modern Art, presided over by Mr. E. F. Kerns, of the Film Library staff. A 
series of early motion pictures, especially selected for their importance in the 
development of the cinematic art, were projected, and preceding each selection 
Miss Iris Barry, of the Museum, discussed the relation of the picture to the 
motion picture art as we know it today. Acknowledgment is due to Miss Barry 
and Mr. Kerns, and to Mr. John Abbott, curator of the Film Library, for their 
kindness in arranging this session. 

The morning session of Wednesday, October 28th, opened with a paper by 
Harold Burns-Meyer on special applications of sound under the title, "Sound 
Control in the Theater Comes of Age." This was followed by an interesting 
paper by Messrs. E. M. Honan-and C. R. Keith, of ERPI, discussing the various 
types of sound-tracks used by the motion picture industry. A feature of the 
session was the report of the Theater Engineering Committee of the Society. Dr. 
Alfred N. Goldsmith, Chairman, which included reports from the sub-committees 



398 HIGHLIGHTS OF THE FALL MEETING (J. S. M. P. E. 

on Projection Practice and on Civilian Defense in Theaters. The latter sub- 
committee has only recently been established, and its studies of the problems of 
air-raids and black-outs, etc., are expected to be noteworthy contributions to the 
industry. The report of the Projection Practice Sub-Committee included an 
extremely valuable discussion of the problems involved in various mechanical 
systems that have recently been proposed for conserving motion picture film. 

Other papers of the Wednesday morning session were two by Messrs. E. K. 
Carver, R. H. Talbot, and H. A. Loomis, of the Eastman Kodak Company, 
on the effect of high gate temperatures in 35-mm projection and on the effect of 
film distortion upon the quality of projection. These two papers provide very 
valuable studies of some serious problems that have been facing the industry. 

The afternoon of Wednesday was devoted principally to processing and labo- 
ratory problems. R. O. Drew and L. T. Sachtleben, of RCA, presented some 
recent laboratory studies of optical reduction printing, followed by a paper by 
D. B. Alnutt, of the Mallinckrodt Chemical Works on "Some Characteristics of 
Ammonium Thiosulfate Fixing Baths." Other papers, by Messrs. Evans, 
Hanson, and Glasoe, and Messrs. Crabtree, Eaton, and Muehler, all of the 
Eastman Kodak Company, dealt with the questions of copper and sulfide in 
developers, tHe accumulation of iodide in developers, and the effect of the com- 
position of processing solutions upon the removal of silver from photographic 
materials. The session concluded with a paper by S. C. Coroniti and H. S. 
Baldwin, of Agfa, describing a precision recording instrument for measuring film 
width. 

The Fifty-Second Semi-Annual Banquet and Dance of the Society was held 
in the Georgian Room of the Hotel in the evening (Wednesday, October 28th), 
Mr. Williford presiding. The officers and governors-elect for 1943 were intro- 
duced, followed by the presentation of the 1941 Journal Award certificates to Mr. 
W. J. Albersheim and Donald MacKenzie for their paper entitled "Analysis 
of Sound-Film Drives," published in the July, 1941, issue of the JOURNAL. 

Both morning and afternoon sessions of Thursday, October 29th, were devoted 
to a symposium on the production of 16-mm motion pictures, and included papers 
on practically all phases of this important branch of the industry. The morning 
session, presided over by Mr. Ralph E. Farnham, opened with an introduction 
by John A. Maurer, followed by papers on production planning, direct 16-mm 
laboratory work, and general 16-mm laboratory practice, by Messrs. R. C. Hoi- 
slag, Lloyd Thompson, and Wm. H. Offenhauser. 

In the afternoon, with Mr. Frank E. Carlson presiding, papers were presented 
dealing with 16-mm recording, 16-mm editing and photographic embellishment, 
carbon arc projection of 16-mm film, 16-mm screen illumination, and on applica- 
tions and distribution problems of 16-mm pictures by Messrs. J. A. Maurer, 
L. Sherwood, F. E. Carlson, W. C. Kalb, and F. W. Bright. This symposium of 
nine papers on 16-mm motion picture production is a valuable companion to the 
symposium on 35-mm production held at the Hollywood Convention last Spring. 

The closing session of the three-day meeting was held at the U. S. Army Signal 
Corps Photographic Center at Astoria, Long Island, by courtesy of Col. M. E. 
Gillette, commanding. The evening opened with a paper by Capt. E. M. 
Watson, of Watervliet Arsenal, on the analysis of fast motion by means of motion 
pictures. Interesting slides and motion pictures taken at very high speed supple- 



Dec., 1942] HIGHLIGHTS OF THE FALL MEETING 

mented the paper. Following this, papers were presented by M. S. David, of the 
General Motors Corp., and Norman Matthews, of Bell Aircraft Corp., on addi- 
tional applications of motion pictures in wartime training of industrial employees 
and men in the Service. 

After a showing of some films that had been shot in the Astoria studio years ago 
by Paramount, long before the studio had been taken over and revamped by the 
Signal Corps, the evening concluded with a conducted tour through all the facili- 
ties of the studio. 

The Society wishes to acknowledge its gratitude to the large number of persons 
and companies who collaborated in providing the various facilities for the Meet- 
ing. Acknowledgment is due also to the Capitol Theater, the Radio City Music 
Hall, the Roxy Theater, Warner's Strand Theater, and the Paramount Theater 
for the passes issued to SMPE delegates during the dates of the Meeting. 



SOCIETY ANNOUNCEMENTS 

OFFICERS AND GOVERNORS FOR 1943 

As a result of the elections held at the recent Fifty-Second Semi-Annual Meet- 
ing at the Hotel Pennsylvania, New York. October 27th to 29th, the following will 
be the list of officers and governors of the Society beginning January 1st: 

** President: HERBERT GRIFFIN 
** Past-President: EMERY HUSE 
** Executive Vice-P resident: LOREN L. RYDER 

* Engineering Vice-President: DONALD E. HYNDMAN 
** Editorial Vice-President: ARTHUR C. DOWNES 

* Financial Vice-President: ARTHUR S. DICKINSON 
** Convention Vice-President: WILLIAM C. KUNZMANN 

* Secretary: E. ALLAN WILLIFORD 

* Treasurer: M. R. BOYER 
Governors: * H. D. BRADBURY 

* FRANK E. CARLSON 

* A. M. GUNDELFINGER 

* EDWARD M. HONAN 

* JOHN A. MAURER 

** WILLIAM A. MUELLER 

* HOLLIS W. MOYSE 
** H. W. REMERSHIED 
** JOSEPH H. SPRAY 
** REEVE O. STROCK 

Additional members of the Board of Governors are the Chairmen of the three 
Local Sections of the Society: 

* Atlantic Coast Section: ALFRED N. GOLDSMITH 

* Pacific Coast Section : CHARLES W. HANDLEY 

Election results for the Mid- West Section will be available shortly. 

ADMISSIONS COMMITTEE 

At a recent meeting of the Admissions Committee, the following applicants for 
membership were admitted into the Society in the Associate grade: 
CULL, R. A. GOETZ, ALEXANDER 

5743 Irving Park Rd., Rare Metals Institute, 

Chicago, 111. Calif. Institute of Technology, 

Pasadena, Calif. 



* Term expires December 31, 1943. 
** Term expires December 31, 1944. 



400 



SOCIETY ANNOUNCEMENTS 401 

HOMSANY, EMIL F. KNOWLES, GERALD L. 

1405 8th Ave.. 1041 1 Oletha Lane, 

Brooklyn, N. Y West Los Angeles, Calif. 

ROSEN, NORMAN 
28-17 38th Ave., 

Long Island City, N. Y. 

In addition, the following applicants have been admitted to the Active grade: 

ASHCRAFT, C S. CASPAR, BELA 

47-31 35th St., 1050 Cahuenga Blvd., 

Long Island City, N. Y. Hollywood, Calif. 

BENNETT, M. F. PULMAN, ROBERT 

Warner Bros. Pictures, Inc., 12-A Brunswick Rd., 

321 West 44th St., Sutton, Surrey, England 
New York, N. Y. 

TELLING, MARTINUS 
Camp-N 

Sherbrooke, Quebec, 
Canada 

The following applicant was admitted to the Student Membership grade: 

HUFFORD, ROBERT GRAY 
Clemson A. & M. College, 
Clemson, S. C. 

The following members were transferred from Associate to Active grade: 

BACH, WALTER THOMPSON, LLOYD 

E. M. Berndt Corp., The Calvin Company, 

5515 Sunset Blvd., 26th & Jefferson Sts.. 

Hollywood, Calif. Kansas City, Mo. 



JOURNAL 

OF THE SOCIETY OF 

MOTION PICTURE ENGINEERS 






AUTHOR AND CLASSIFIED 
INDEXES 

VOLUME XXXVIII 
JULY-DECEMBER, 1042 



AUTHOR INDEX, VOLUME XXXIX 



JULY TO DECEMBER, 1942 



Author 
BAUMBACH, H. L. 



BECKER, L. S. 

BOYLE, J. W. 

BRECHA, H. C. 

BROWN, B. B. 

BROWN, F. W. 
(and A. GOETZ) 

CAMPBELL, R. L. 

(and KESSLER, R. E., and 
RUTHERFORD, R. E., and 
LANDSBERG, K. V.) 

CLARKE, C. G. 

EXXON, W., JR. 

FULLER, R. B. 

(and RHODES, L. S.) 
GARITY, W. E. 

(and JONES, WATSON) 
GOETZ, A. (and BROWN, 

F. W.) 

GlTTERMAN, HENRY 



GOLDSMITH, L. T. 
HENDERSON, R. W. 

HOCH, W. 
IRSKY, G. L. 

JONES, WATSON 

(and GARITY, W. E.) 
KELLOGG, E. W. 

(and MASTERSON, E. E.) 
404 



Issue Page 

Continuous Replenishment and Chem- 
ical Control of Motion Picture De- 
veloping Solutions July 55 
Technology in the Art of Producing 

Motion Pictures Aug. 109 

Black-and-White Cinematography Aug. 83 

Wright Field Training Film Laboratory Dec. 348 

Prescoring and Scoring Oct. 228 
Light-Scattering by Graininess of 

Photographic Emulsions Dec. 375 

Mobile Television Equipment July 22 



Putting Clouds into Exterior Scenes Aug. 92 

The Navy's Utilization of Film for 
Training Purposes Dec. 333 

Production of 16-Mm Motion Pictures 

for Television Projection Sept. 195 

Experiences in Road-Showing Walt 

Disney's Fantasia July 6 

Light-Scattering by Graininess of 

Photographic Emulsions Dec. 375 

A New Electrostatic Air-Cleaner and 
Its Application to the Motion Pic- 
ture Industry July 70 

Re-Recording Sound Motion Pictures Nov. 277 

Developments in Time-Saving Process 

Projection Equipment Oct. 245 

Technicolor Cinematography Aug. 96 

The Documentary, Scientific, and Mili- 
tary Films of the Soviet Union Dec. 353 

Experiences in Road-Showing Walt Dis- 
ney's Fantasia July 6 

A Study of Flicker in 16-Mm Picture 

Projection Oct. 232 



INDI-X 



405 



Author 

KESSLER, R. E. 

(and CAMPBELL, R. L., 
and RUTHERFORD, R. E., 
and LANDSBERG, K. V.) 

LANDSBERG, K. V., 
(and CAMPBELL, R. L., 
and KESSLER, R. E., 
and RUTHERFORD, R. E.) 

Lo, T. Y. 

LUBCKE, H. R. 

MASTERSON, E. E. 

(and KELLOGG, E. W.) 
MILLER, B. F. 



O'CONNELL, L. W. 

OFFENHAUSER, W. H., JR. 

PLUMB, EDWARD H. 

RETTINGER, M. 

RHODES, L. S. 

(and FULLER, R. B.) 

RUTHERFORD, R. E. 
(and CAMPBELL, R. L., 
and KESSLER, R. E., 
and LANDSBERG, K. V.) 

SACHTLEBEN, L. T. 

SlLVERTOOTH, E. W. 

SMITH, F. Y. 
STOTT, JOHN G. 
TASKER, H. G. 
THOMPSON, L. 

WILKINSON, J. R. 
WILLIFORD, E. A. 

Wrrr. H. A. 



Issue Page 
Mobile Television Kquipment July 22 



Mobile Television Equipment July 22 



The Underground Motion Picture In- 
dustry in China Dec. -t J I 

The Engineering Aspect of Portable 

Television Pick-Ups. Dec. 384 

A Study of Flicker in 16-Mm Picture 

Projection Oct. 232 

Elimination of Relative Spectral En- 
ergy Distortion in Electronic Com- 
pressors Nov. :<17 

The Photographing of 16-Mm Koda- 
chrome Short Subjects for Major 
Studio Release Nov. :H4 

A Review of the Question of 16-Mm 

Emulsion Position Aug. 123 

The Future of Fantasound July lf> 

A Modern Music Recording Studio Sept. 18T 

Production of 16-Mm Motion Pictures 

for Television Projection Sept. 195 

Mobile Television Equipment July 22 



A One-Ray System for Designing 

Spherical Condensers Dec 

Stop Calibration of Photographic Ob- 
jectives Aug. 1 19 

The Cutting and Editing of Motion 

Pictures Nov. 24 

The Application of Potent iomvtr it- 
Methods to Developer Analysis July 

The Technique of Production Sound 

Recording Oct. LM.'i 

The Production of Industrial Motion 

Pictures Aug. 135 

Motion Picture Laboratory Practices Sept. 166 

The Carbon Situation and Copper 

Conservation July 3 

The Practical Aspect of Edge- Number- 
ing 16-Mm Film July 



CLASSIFIED INDEX, VOLUME XXXIX 

JULY TO DECEMBER 1942 

Air Cleaners 

A New Electrostatic Air-Cleaner and Its Application to the Motion Picture 
Industry, Henry Gitterman, No. 1 (July), p. 70. 

Apparatus 

A New Electrostatic Air-Cleaner and Its Application to the Motion Picture 

Industry, Henry Gitterman, No. 1 (July), p. 70. 

Developments in Time-Saving Process Projection Equipment, R. W. Hender- 
son, No. 4 (Oct.), p. 245. 

Arcs 

The Carbon Situation and Copper Conservation, E. A. Williford, No. 1 (July), 
p. 3. 

Army, U. S. 

Wright Field Training Film Laboratory, H. C. Brecha, No. 6 (Dec.), p. 348. 

Atlantic Coast Section 

The Carbon Situation and Copper Conservation, E. A. Williford, No. 1 (July), 
p. 3. 

Cameras 

Stop Calibration of Photographic Objectives, E. W. Silvertooth, No. 2 (Aug.), 
p. 119. 

Carbons 

The Carbon Situation and Copper Conservation, E. A. Williford, No. 1 (July), 
p. 3. 

Cartoons 

Experiences in Road-Showing Walt Disney's Fantasia, W. E. Garity and Wat- 
son Jones, No. 1 (July), p. 6. 
The Future of Fantasound, Edward H. Plumb, No. 1 (July), p. 16. 

China, Motion Pictures in 

The Underground Motion Picture Industry in China, T. Y. Lo, No. 6 (Dec.), 
p. 341. 

Cinematography 

Black-and-White Cinematography, J. W. Boyle, No. 2 (Aug.), p. 83. 
Putting Clouds into Exterior Scenes, C. G. Clarke, No. 2 (Aug.), p. 92. 
Technicolor Cinematography, W. Hoch, No. 2 (Aug.), p. 96. 
Stop Calibration of Photographic Objectives, E, W. Silvertooth, No. 2 (Aug.), 
p. 119. 

406 



INDEX 407 

The Photographing of 16-Mm Kodachrome Short Subjects for Major Studio 
Release, L. W. O'Connell, No. 5 (Nov.), p. 31 I 

Color Cinematography 

Technicolor Cinematography, W. Hoch, No. 2 (Aug.), p. 96. 
The Photographing of 16-Mm Kodachrome Short Subjects for Major Studio 
Release, L. W. O'Connell, No. 5 (Nov.), p. 314. 

Committee Reports 

Projection Practice, No. 4 (Sept.), p. 149. 
Progress, No. 5 (Nov.), p. 3. 

Compressors, Electronic 

Elimination of Relative Spectral Energy Distortion in Electronic Compressors, 
B. F. Miller, No. 5 (Nov.), p. 317. 

Condensers, Optical 

A One-Ray System for Designing Spherical Condensers, L. T. Sachtleben, No. 
6 (Dec.), P. 358. 

Conservation 

The Carbon Situation and Copper Conservation, E. A. Williford, No. 1 (July). 
p. 3. 

Control 
(See Processing, Control of.) 

Copper 

The Carbon Situation and Copper Conservation, E. A. Williford, No. 1 (July), 
p. 3. 

Cutting Motion Pictures 
The Cutting and Editing of Motion Pictures, F. Y. Smith, No. 5 (Nov.), p. 284. 

Developers 
The Application of Potentiometric Methods to Developer Analysis, John G. 

Stott, No. 1 (July), p. 37. 

Continuous Replenishment and Chemical Control of Motion Picture Develop- 
ing Solutions, H. L. Baumbach, No. 1 (July), p. 65. 

Distortion, Sound 

Elimination of Relative Spectral Energy Distortion in Electronic Compressors. 
B. F. Miller, No. 5 (Nov.), p. 317. 

Editing Motion Pictures 

The Cutting and Editing of Motion Pictures, F. Y. Smith, No. 5 (Nov.), p. 284. 

Edge-Numbering 

The Practical Aspect of Edge-Numbering 16-Mm Film, H. A. Witt. No. 1 

(July), p. 67. 



408 INDEX [j. s. M. P. E. 

Educational Motion Pictures 

The Navy's Utilization of Film for Training Purposes, Wm. Exton, Jr., No. 6 

(Dec.), p. 333. 
The Underground Motion Picture Industry in China, T. Y. Lo, No. 6 (Dec.), 

p. 341. 

Wright Field Training Film Laboratory, H. C. Brecha, No. 6 (Dec.), p. 348. 
The Documentary, Scientific, and Military Films of the Soviet Union, Gregory 

L. Irsky, No. 6 (Dec.), p. 353. 

Emulsions 

Light-Scattering by Graininess of Photographic Emulsions, Alexander Goetz 
and F. W. Brown, No. 6 (Dec.), p. 375. 

Fantasia 

Experiences in Road-Showing Walt Disney's Fantasia, W. E. Garity and Wat- 
son Jones, No. 1 (July), p. 6. 

Fantasound 

Experiences in Road-Showing Walt Disney's Fantasia, W. E. Garity and Wat- 
son Jones, No. 1 (July), p. 6. 
The Future of Fantasound, Edward H. Plumb, No. 1 (July), p. 16. 

Flicker 

A Study of Flicker in 16-Mm Picture Projection, E. E. Masterson and E. W. 
Kellogg, No. 5 (Oct.), p. 232. 

General 

The Future of Fantasound, Edward H. Plumb, No. 1 (July), p. 16. 
Technology in the Art of Producing Motion Pictures, L. S. Becker, No. 2 (Aug.), 

p. 109. 
The Navy's Utilization of Film for Training Purposes, William Exton, Jr., No. 6 

(Dec.), p. 333. 
The Underground Motion Picture Industry in China, T. Y. Lo, No. 6 (Dec.), p. 

341. 

Wright Field Training Film Laboratory, H. C. Brecha, No. 6 (Dec.), p. 348. 
The Documentary, Scientific, and Military Films of the Soviet Union, Gregory 

L. Irsky, No. 6 (Dec.), p. 353. 

Historical 

Progress in the Motion Picture Industry: Report of the Progress Committee 
for 1940-41, No. 5 (Nov.), p. 294. 

Index 

Author: July-December, 1942, No. 6 (Dec.), p. 404. 
Classified: July-December, 1942, No. 6 (Dec.), p. 406. 

Industrial Motion Pictures 

The Production of Industrial Motion Pictures, L. Thompson, No. 2 (Aug.), p. 
135. 

Kodachrome 

The Photographing of 16-Mm Kodachrome Short Subjects for Major Studio 
Release, L. W. O'Connell, No. 5 (Nov.), p. 314. 



Dec., 1942] I NDEX .,,, 

Laboratory Practice 

Motion Picture Laboratory Practices, J. R. Wilkinson, No. 3 (Sept.), p. 160. 

Light-Scattering 

Light-Scattering by Graininess of Photographic Emulsions, Alexander Goctz 
and F. W. Brown, No. 6 (Dec.), p. 375. 

Navy, U. S. 

The Navy's Utilization of Film for Training Purposes. William Exton, Jr., No. 
6 (Dec.), p. 333. 

Non-Theatrical Motion Pictures 
( See Sixteen- Millimeter. ) 

Optics 

Stop Calibration of Photographic Objectives, E. W. Silvertooth, No. 2 (Aug.), 

p. 119. 
A One-Ray System for Designing Spherical Condensers, L. T. Sachtleben, No. 

6 (Dec.), p. 358. 

Portable Equipment 

Experiences in Road-Showing Walt Disney's Fantasia, W. E. Garity and Wat- 
son Jones, No. 1 (July), p. 6. 
The Engineering Aspect of Portable Television Pick-Ups, H. R. Lubcke, No. 6 

(Dec.), p. 384. 

Prescoring 

Prescoring and Scoring, B. B. Brown, No. 4 (Oct.), p. 228. 

Process Projection 

Developments in Time-Saving Process Projection Equipment, R. W. Hender- 
son, No. 4 (Oct.), p. 245. 

Processing 

Motion Picture Laboratory Practices, J. R. Wilkinson, No. 3 (Sept.). p. 168. 

Processing, Control of 

The Application of Potent iometric Methods to Developer Analysts. John C. 

Stott, No. 1 (July), p. 37. 

Continuous Replenishment and Chemical Control of Motion Picture Develop- 
ing Solutions, H. L. Baumbach, No. 1 (July), p. 65. 

Production 

The Production of Industrial Motion Pictures, L. Thompson. No. 2 (Aug.). 

p. 135. 
Production of 16-Mm Motion Pictures for Television Projection. R. B. Fuller 

and L. S. Rhodes, No. 3 (Sept.), p. 195. 

Progress 

Progress in the Motion Picture Industry: Report of the Progress Commit tcr 
for 1940-41, No. 5 (Nov.), p. 294. 



410 INDEX [J. S. M. P. E. 

Projection 

The Carbon Situation and Copper Conservation, E. A. Williford, No. 1 (July), 
p. 3. 

Report of the Projection Practice Sub-Committee of the Theater Engineering 
Committee: Projection Room Plans, No. 3 (Sept. ), p. 149. 

A Study of Flicker in 16-Mm Picture Projection, E. E. Masterson and E. W. 
Kellogg, No. 4 (Oct.), p. 232. 

Developments in Time-Saving Process Projection Equipment, R. W. Hender- 
son, No. 4 (Oct.), p. 245. 

Projection Practice 

The Carbon Situation and Copper Conservation, E. A. Williford, No. 1 (July), 

p. 3. 
Report of the Projection Practice Sub- Committee of the Theater Engineering 

Committee: Projection Room Plans, No. 3 (Sept.), p. 149. 

Recording Stages 

A Modern Music Recording Studio, M. Rettinger, No. 3 (Sept.), p. 186. 

Re-Recording 

Re-Recording Sound Motion Pictures, L. T. Goldsmith, No. 5 (Nov.), p. 277. 

Replenishment 

Continuous Replenishment and Chemical Control of Motion Picture Develop- 
ing Solutions, H. L. Baumbach, No. 1 (July), p. 55. 

Scoring 

Prescoring and Scoring, B. B. Brown, No. 4 (Oct.), p. 228. 

Sixteen-Millimeter 

The Practical Aspect of Edge-Numbering 16-Mm Film, H. A. Witt, No. 1 

(July), p. 67. 
A Review of the Question of 16-Mm Emulsion Position, W. H. Offenhauser, 

Jr., No. 2 (Aug.), p. 123. 
The Production of Industrial Motion Pictures, L. Thompson, No. 2 (Aug.), p. 

135. 
Production of 16-Mm Motion Pictures for Television Projection, R. B. Fuller 

and L. S. Rhodes, No. 3 (Sept.), p. 195. 
A Study of Flicker in 16-Mm Picture Projection, E. E. Masterson and E. W. 

Kellogg, No. 4 (Oct.), p. 232. 
The Photographing of 16-Mm Kodachrome Short Subjects for Major Studio 

Release, L. W. O'Connell, No. 5 (Nov.), p. 314. 

Sound Reproduction 

Experiences in Road-Showing Walt Disney's Fantasia, W. E. Garity and Wat- 
son Jones, No. 1 (July), p. 6. 

The Future of Fantasound, Edward H. Plumb, No. 1 (July), p. 16. 

A Modern Music Recording Studio, M. Rettinger, No. 3 (Sept.), p. 186. 

The Technique of Production Sound Recording, H. G. Tasker, No. 4 (Oct.), p. 
213. 

Prescoring and Scoring, B. B. Brown, No. 4 (Oct.), p. 228. 



Dec., 1942] INDEX 411 

Re-Recording Sound Motion Pictures, L. T. Goldsmith, No. 5 (Nov.). p. 277. 
Elimination of Relative Spectral Energy Distortion in Electronic Compressors, 
B. F. Miller, No. 5 (Nov.), p. 317. 

Special Effects Cinematography 

Black-and-White Cinematography, J. W. Boyle, No. 2 (Aug.), p. 83. 
Putting Clouds into Exterior Scenes, C. G. Clarke, No. 2 (Aug.), p. 92. 
Technicolor Cinematography, W. Hoch, No. 2 (Aug.), p. 96. 

Standardization 

The Practical Aspect of Edge-Numbering 16-Mm Film, H. A. Witt, No. 1 (July), 

p. 67. 
A Review of the Question of 16-Mm Emulsion Position, Wm. H. OfTcnhauscr, 

Jr., No. 2 (Aug.), p. 123. 
Report of the Projection Practice Sub-Committee of the Theater Engineering 

Committee: Projection Room Plans, No. 3 (Sept.), p. 149. 
Production of 16-Mm Motion Pictures for Television Projection, R. B. Fuller 

and L. S. Rhodes, No. 3 (Sept.), p. 195. 

Studio Practice 

Black-and-White Cinematography, J. W. Boyle, No. 2 (Aug.), p. 83. 

Putting Clouds into Exterior Scenes, C. G. Clarke, No. 2 (Aug.), p. 92. 

Technicolor Cinematography, W. Hoch, No. 2 (Aug.), p. 96. 

Technology in the Art of Producing Motion Pictures, L. S. Becker. No. 2 (Aug.), 
p. 109. 

Stop Calibration of Photographic Objectives, E. W. Silvertooth, No. 2 (Aug.), 
p. 119. 

A Review of the Question of 16-Mm Emulsion Position, W. H. Offnehauser, Jr.. 
No. 2 (Aug.), p. 123. 

A Modern Music Recording Studio, M. Rettinger, No. 3 (Sept.), p. 186. 

The Technique of Production Sound Recording, H. G. Tasker, No. 4 (Oct.), p. 
213. 

Prescoring and Scoring, B. B. Brown, No. 4 (Oct.), p. 228. 

Developments in Time-Saving Process Projection Equipment, R. W. Hender- 
son, No. 4 (Oct.), p. 245. 

Re-Recording Sound Motion Pictures, L. T. Goldsmith, No. 5 (Nov.). p. 277 

The Cutting and Editing of Motion Pictures, F. Y. Smith, No. 5 (Nov.), p. 284. 

Technicolor 

Technicolor Cinematography, W. Hoch, No. 2 (Aug.), p. 96. 

Technology of Motion Pictures 

Technology in the Art of Producing Motion Pictures, L. S. Becker, No. 2 (Aug.). 
p. 109. 

Television 

Mobile Television Equipment, -R. L. Campbell, R. E. Kessler, R. E. Rutherford. 

and K. V. Landsberg, No. 1 (July), p. 22. 
Production of 16-Mm Motion Pictures for Television Projection. R. B. Fuller 

and L. S. Rhodes, No. 3 (Sept.), p. 195. 



412 INDEX 

The Engineering Aspect of Portable Television Pick-Ups, H. R. Lubcke, No. 6 
(Dec.), P. 384. 

Theater Engineering Committee 

Report of the Projection Practice Sub-Committee of the Theater Engineering 
Committee: Projection Room Plans, No. 3 (Sept.), p. 149. 

Training Films 

The Navy's Utilization of Film for Training Purposes, William Exton, Jr., No. 6 

(Dec.), p. 333. 

Wright Field Training Film Laboratory, H. C. Brecha, No. 6 (Dec.), p. 348. 
The Documentary, Scientific, and Military Films of the Soviet Union, Gregory 

L. Irsky, No. 6 (Dec.), p. 353. 

Trick Photography 

Putting Clouds into Exterior Scenes, C. G. Clarke, No. 2 (Aug.), p. 92. 
Developments in Time-Saving Process Projection Equipment, R. W. Hender- 
son, No. 4 (Oct.), p. 245. 

U.S.S.R., Motion Pictures in 

The Documentary, Scientific, and Military Films of the Soviet Union, Gregory 
L. Irsky, No. 6 (Dec.), p. 353. 



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